Merge pull request #5307 from ziglang/self-hosted-incremental-compilation

rework self-hosted compiler for incremental builds

README.md

@@ -71,40 +71,3 @@ can do about it. See that issue for a workaround you can do in the meantime.
 ##### Windows
 
 See https://github.com/ziglang/zig/wiki/Building-Zig-on-Windows
-
-### Stage 2: Build Self-Hosted Zig from Zig Source Code
-
-*Note: Stage 2 compiler is not complete. Beta users of Zig should use the
-Stage 1 compiler for now.*
-
-Dependencies are the same as Stage 1, except now you can use stage 1 to compile
-Zig code.
-
-```
-bin/zig build --prefix $(pwd)/stage2
-```
-
-This produces `./stage2/bin/zig` which can be used for testing and development.
-Once it is feature complete, it will be used to build stage 3 - the final compiler
-binary.
-
-### Stage 3: Rebuild Self-Hosted Zig Using the Self-Hosted Compiler
-
-*Note: Stage 2 compiler is not yet able to build Stage 3. Building Stage 3 is
-not yet supported.*
-
-Once the self-hosted compiler can build itself, this will be the actual
-compiler binary that we will install to the system. Until then, users should
-use stage 1.
-
-#### Debug / Development Build
-
-```
-./stage2/bin/zig build --prefix $(pwd)/stage3
-```
-
-#### Release / Install Build
-
-```
-./stage2/bin/zig build install -Drelease
-```

build.zig

@@ -51,6 +51,8 @@ pub fn build(b: *Builder) !void {
 
     var exe = b.addExecutable("zig", "src-self-hosted/main.zig");
     exe.setBuildMode(mode);
+    test_step.dependOn(&exe.step);
+    b.default_step.dependOn(&exe.step);
 
     const skip_release = b.option(bool, "skip-release", "Main test suite skips release builds") orelse false;
     const skip_release_small = b.option(bool, "skip-release-small", "Main test suite skips release-small builds") orelse skip_release;
@@ -58,21 +60,20 @@ pub fn build(b: *Builder) !void {
     const skip_release_safe = b.option(bool, "skip-release-safe", "Main test suite skips release-safe builds") orelse skip_release;
     const skip_non_native = b.option(bool, "skip-non-native", "Main test suite skips non-native builds") orelse false;
     const skip_libc = b.option(bool, "skip-libc", "Main test suite skips tests that link libc") orelse false;
-    const skip_self_hosted = (b.option(bool, "skip-self-hosted", "Main test suite skips building self hosted compiler") orelse false) or true; // TODO evented I/O good enough that this passes everywhere
-    if (!skip_self_hosted) {
-        test_step.dependOn(&exe.step);
-    }
 
     const only_install_lib_files = b.option(bool, "lib-files-only", "Only install library files") orelse false;
-    if (!only_install_lib_files and !skip_self_hosted) {
+    const enable_llvm = b.option(bool, "enable-llvm", "Build self-hosted compiler with LLVM backend enabled") orelse false;
+    if (enable_llvm) {
         var ctx = parseConfigH(b, config_h_text);
         ctx.llvm = try findLLVM(b, ctx.llvm_config_exe);
 
         try configureStage2(b, exe, ctx);
-
-        b.default_step.dependOn(&exe.step);
+    }
+    if (!only_install_lib_files) {
         exe.install();
     }
+    const link_libc = b.option(bool, "force-link-libc", "Force self-hosted compiler to link libc") orelse false;
+    if (link_libc) exe.linkLibC();
 
     b.installDirectory(InstallDirectoryOptions{
         .source_dir = "lib",

lib/std/array_list.zig

@@ -8,13 +8,13 @@ const Allocator = mem.Allocator;
 /// A contiguous, growable list of items in memory.
 /// This is a wrapper around an array of T values. Initialize with `init`.
 pub fn ArrayList(comptime T: type) type {
-    return AlignedArrayList(T, null);
+    return ArrayListAligned(T, null);
 }
 
-pub fn AlignedArrayList(comptime T: type, comptime alignment: ?u29) type {
+pub fn ArrayListAligned(comptime T: type, comptime alignment: ?u29) type {
     if (alignment) |a| {
         if (a == @alignOf(T)) {
-            return AlignedArrayList(T, null);
+            return ArrayListAligned(T, null);
         }
     }
     return struct {
@@ -76,6 +76,10 @@ pub fn AlignedArrayList(comptime T: type, comptime alignment: ?u29) type {
             };
         }
 
+        pub fn toUnmanaged(self: Self) ArrayListAlignedUnmanaged(T, alignment) {
+            return .{ .items = self.items, .capacity = self.capacity };
+        }
+
         /// The caller owns the returned memory. ArrayList becomes empty.
         pub fn toOwnedSlice(self: *Self) Slice {
             const allocator = self.allocator;
@@ -84,8 +88,8 @@ pub fn AlignedArrayList(comptime T: type, comptime alignment: ?u29) type {
             return result;
         }
 
-        /// Insert `item` at index `n`. Moves `list[n .. list.len]`
-        /// to make room.
+        /// Insert `item` at index `n` by moving `list[n .. list.len]` to make room.
+        /// This operation is O(N).
         pub fn insert(self: *Self, n: usize, item: T) !void {
             try self.ensureCapacity(self.items.len + 1);
             self.items.len += 1;
@@ -94,8 +98,7 @@ pub fn AlignedArrayList(comptime T: type, comptime alignment: ?u29) type {
             self.items[n] = item;
         }
 
-        /// Insert slice `items` at index `i`. Moves
-        /// `list[i .. list.len]` to make room.
+        /// Insert slice `items` at index `i` by moving `list[i .. list.len]` to make room.
         /// This operation is O(N).
         pub fn insertSlice(self: *Self, i: usize, items: SliceConst) !void {
             try self.ensureCapacity(self.items.len + items.len);
@@ -146,10 +149,15 @@ pub fn AlignedArrayList(comptime T: type, comptime alignment: ?u29) type {
         /// Append the slice of items to the list. Allocates more
         /// memory as necessary.
         pub fn appendSlice(self: *Self, items: SliceConst) !void {
+            try self.ensureCapacity(self.items.len + items.len);
+            self.appendSliceAssumeCapacity(items);
+        }
+
+        /// Append the slice of items to the list, asserting the capacity is already
+        /// enough to store the new items.
+        pub fn appendSliceAssumeCapacity(self: *Self, items: SliceConst) void {
             const oldlen = self.items.len;
             const newlen = self.items.len + items.len;
-
-            try self.ensureCapacity(newlen);
             self.items.len = newlen;
             mem.copy(T, self.items[oldlen..], items);
         }
@@ -259,6 +267,231 @@ pub fn AlignedArrayList(comptime T: type, comptime alignment: ?u29) type {
     };
 }
 
+/// Bring-your-own allocator with every function call.
+/// Initialize directly and deinitialize with `deinit` or use `toOwnedSlice`.
+pub fn ArrayListUnmanaged(comptime T: type) type {
+    return ArrayListAlignedUnmanaged(T, null);
+}
+
+pub fn ArrayListAlignedUnmanaged(comptime T: type, comptime alignment: ?u29) type {
+    if (alignment) |a| {
+        if (a == @alignOf(T)) {
+            return ArrayListAlignedUnmanaged(T, null);
+        }
+    }
+    return struct {
+        const Self = @This();
+
+        /// Content of the ArrayList.
+        items: Slice = &[_]T{},
+        capacity: usize = 0,
+
+        pub const Slice = if (alignment) |a| ([]align(a) T) else []T;
+        pub const SliceConst = if (alignment) |a| ([]align(a) const T) else []const T;
+
+        /// Initialize with capacity to hold at least num elements.
+        /// Deinitialize with `deinit` or use `toOwnedSlice`.
+        pub fn initCapacity(allocator: *Allocator, num: usize) !Self {
+            var self = Self.init(allocator);
+            try self.ensureCapacity(allocator, num);
+            return self;
+        }
+
+        /// Release all allocated memory.
+        pub fn deinit(self: *Self, allocator: *Allocator) void {
+            allocator.free(self.allocatedSlice());
+            self.* = undefined;
+        }
+
+        pub fn toManaged(self: *Self, allocator: *Allocator) ArrayListAligned(T, alignment) {
+            return .{ .items = self.items, .capacity = self.capacity, .allocator = allocator };
+        }
+
+        /// The caller owns the returned memory. ArrayList becomes empty.
+        pub fn toOwnedSlice(self: *Self, allocator: *Allocator) Slice {
+            const result = allocator.shrink(self.allocatedSlice(), self.items.len);
+            self.* = Self{};
+            return result;
+        }
+
+        /// Insert `item` at index `n`. Moves `list[n .. list.len]`
+        /// to make room.
+        pub fn insert(self: *Self, allocator: *Allocator, n: usize, item: T) !void {
+            try self.ensureCapacity(allocator, self.items.len + 1);
+            self.items.len += 1;
+
+            mem.copyBackwards(T, self.items[n + 1 .. self.items.len], self.items[n .. self.items.len - 1]);
+            self.items[n] = item;
+        }
+
+        /// Insert slice `items` at index `i`. Moves
+        /// `list[i .. list.len]` to make room.
+        /// This operation is O(N).
+        pub fn insertSlice(self: *Self, allocator: *Allocator, i: usize, items: SliceConst) !void {
+            try self.ensureCapacity(allocator, self.items.len + items.len);
+            self.items.len += items.len;
+
+            mem.copyBackwards(T, self.items[i + items.len .. self.items.len], self.items[i .. self.items.len - items.len]);
+            mem.copy(T, self.items[i .. i + items.len], items);
+        }
+
+        /// Extend the list by 1 element. Allocates more memory as necessary.
+        pub fn append(self: *Self, allocator: *Allocator, item: T) !void {
+            const new_item_ptr = try self.addOne(allocator);
+            new_item_ptr.* = item;
+        }
+
+        /// Extend the list by 1 element, but asserting `self.capacity`
+        /// is sufficient to hold an additional item.
+        pub fn appendAssumeCapacity(self: *Self, item: T) void {
+            const new_item_ptr = self.addOneAssumeCapacity();
+            new_item_ptr.* = item;
+        }
+
+        /// Remove the element at index `i` from the list and return its value.
+        /// Asserts the array has at least one item.
+        /// This operation is O(N).
+        pub fn orderedRemove(self: *Self, i: usize) T {
+            const newlen = self.items.len - 1;
+            if (newlen == i) return self.pop();
+
+            const old_item = self.items[i];
+            for (self.items[i..newlen]) |*b, j| b.* = self.items[i + 1 + j];
+            self.items[newlen] = undefined;
+            self.items.len = newlen;
+            return old_item;
+        }
+
+        /// Removes the element at the specified index and returns it.
+        /// The empty slot is filled from the end of the list.
+        /// This operation is O(1).
+        pub fn swapRemove(self: *Self, i: usize) T {
+            if (self.items.len - 1 == i) return self.pop();
+
+            const old_item = self.items[i];
+            self.items[i] = self.pop();
+            return old_item;
+        }
+
+        /// Append the slice of items to the list. Allocates more
+        /// memory as necessary.
+        pub fn appendSlice(self: *Self, allocator: *Allocator, items: SliceConst) !void {
+            try self.ensureCapacity(allocator, self.items.len + items.len);
+            self.appendSliceAssumeCapacity(items);
+        }
+
+        /// Append the slice of items to the list, asserting the capacity is enough
+        /// to store the new items.
+        pub fn appendSliceAssumeCapacity(self: *Self, items: SliceConst) void {
+            const oldlen = self.items.len;
+            const newlen = self.items.len + items.len;
+
+            self.items.len = newlen;
+            mem.copy(T, self.items[oldlen..], items);
+        }
+
+        /// Same as `append` except it returns the number of bytes written, which is always the same
+        /// as `m.len`. The purpose of this function existing is to match `std.io.OutStream` API.
+        /// This function may be called only when `T` is `u8`.
+        fn appendWrite(self: *Self, allocator: *Allocator, m: []const u8) !usize {
+            try self.appendSlice(allocator, m);
+            return m.len;
+        }
+
+        /// Append a value to the list `n` times.
+        /// Allocates more memory as necessary.
+        pub fn appendNTimes(self: *Self, allocator: *Allocator, value: T, n: usize) !void {
+            const old_len = self.items.len;
+            try self.resize(self.items.len + n);
+            mem.set(T, self.items[old_len..self.items.len], value);
+        }
+
+        /// Adjust the list's length to `new_len`.
+        /// Does not initialize added items if any.
+        pub fn resize(self: *Self, allocator: *Allocator, new_len: usize) !void {
+            try self.ensureCapacity(allocator, new_len);
+            self.items.len = new_len;
+        }
+
+        /// Reduce allocated capacity to `new_len`.
+        /// Invalidates element pointers.
+        pub fn shrink(self: *Self, allocator: *Allocator, new_len: usize) void {
+            assert(new_len <= self.items.len);
+
+            self.items = allocator.realloc(self.allocatedSlice(), new_len) catch |e| switch (e) {
+                error.OutOfMemory => { // no problem, capacity is still correct then.
+                    self.items.len = new_len;
+                    return;
+                },
+            };
+            self.capacity = new_len;
+        }
+
+        pub fn ensureCapacity(self: *Self, allocator: *Allocator, new_capacity: usize) !void {
+            var better_capacity = self.capacity;
+            if (better_capacity >= new_capacity) return;
+
+            while (true) {
+                better_capacity += better_capacity / 2 + 8;
+                if (better_capacity >= new_capacity) break;
+            }
+
+            const new_memory = try allocator.realloc(self.allocatedSlice(), better_capacity);
+            self.items.ptr = new_memory.ptr;
+            self.capacity = new_memory.len;
+        }
+
+        /// Increases the array's length to match the full capacity that is already allocated.
+        /// The new elements have `undefined` values.
+        /// This operation does not invalidate any element pointers.
+        pub fn expandToCapacity(self: *Self) void {
+            self.items.len = self.capacity;
+        }
+
+        /// Increase length by 1, returning pointer to the new item.
+        /// The returned pointer becomes invalid when the list is resized.
+        pub fn addOne(self: *Self, allocator: *Allocator) !*T {
+            const newlen = self.items.len + 1;
+            try self.ensureCapacity(allocator, newlen);
+            return self.addOneAssumeCapacity();
+        }
+
+        /// Increase length by 1, returning pointer to the new item.
+        /// Asserts that there is already space for the new item without allocating more.
+        /// The returned pointer becomes invalid when the list is resized.
+        /// This operation does not invalidate any element pointers.
+        pub fn addOneAssumeCapacity(self: *Self) *T {
+            assert(self.items.len < self.capacity);
+
+            self.items.len += 1;
+            return &self.items[self.items.len - 1];
+        }
+
+        /// Remove and return the last element from the list.
+        /// Asserts the list has at least one item.
+        /// This operation does not invalidate any element pointers.
+        pub fn pop(self: *Self) T {
+            const val = self.items[self.items.len - 1];
+            self.items.len -= 1;
+            return val;
+        }
+
+        /// Remove and return the last element from the list.
+        /// If the list is empty, returns `null`.
+        /// This operation does not invalidate any element pointers.
+        pub fn popOrNull(self: *Self) ?T {
+            if (self.items.len == 0) return null;
+            return self.pop();
+        }
+
+        /// For a nicer API, `items.len` is the length, not the capacity.
+        /// This requires "unsafe" slicing.
+        fn allocatedSlice(self: Self) Slice {
+            return self.items.ptr[0..self.capacity];
+        }
+    };
+}
+
 test "std.ArrayList.init" {
     var list = ArrayList(i32).init(testing.allocator);
     defer list.deinit();

lib/std/fifo.zig

@@ -191,8 +191,8 @@ pub fn LinearFifo(
         }
 
         /// Read the next item from the fifo
-        pub fn readItem(self: *Self) !T {
-            if (self.count == 0) return error.EndOfStream;
+        pub fn readItem(self: *Self) ?T {
+            if (self.count == 0) return null;
 
             const c = self.buf[self.head];
             self.discard(1);
@@ -282,7 +282,10 @@ pub fn LinearFifo(
         /// Write a single item to the fifo
         pub fn writeItem(self: *Self, item: T) !void {
             try self.ensureUnusedCapacity(1);
+            return self.writeItemAssumeCapacity(item);
+        }
 
+        pub fn writeItemAssumeCapacity(self: *Self, item: T) void {
             var tail = self.head + self.count;
             if (powers_of_two) {
                 tail &= self.buf.len - 1;
@@ -342,10 +345,10 @@ pub fn LinearFifo(
             }
         }
 
-        /// Peek at the item at `offset`
-        pub fn peekItem(self: Self, offset: usize) error{EndOfStream}!T {
-            if (offset >= self.count)
-                return error.EndOfStream;
+        /// Returns the item at `offset`.
+        /// Asserts offset is within bounds.
+        pub fn peekItem(self: Self, offset: usize) T {
+            assert(offset < self.count);
 
             var index = self.head + offset;
             if (powers_of_two) {
@@ -369,18 +372,18 @@ test "LinearFifo(u8, .Dynamic)" {
     {
         var i: usize = 0;
         while (i < 5) : (i += 1) {
-            try fifo.write(&[_]u8{try fifo.peekItem(i)});
+            try fifo.write(&[_]u8{fifo.peekItem(i)});
         }
         testing.expectEqual(@as(usize, 10), fifo.readableLength());
         testing.expectEqualSlices(u8, "HELLOHELLO", fifo.readableSlice(0));
     }
 
     {
-        testing.expectEqual(@as(u8, 'H'), try fifo.readItem());
-        testing.expectEqual(@as(u8, 'E'), try fifo.readItem());
-        testing.expectEqual(@as(u8, 'L'), try fifo.readItem());
-        testing.expectEqual(@as(u8, 'L'), try fifo.readItem());
-        testing.expectEqual(@as(u8, 'O'), try fifo.readItem());
+        testing.expectEqual(@as(u8, 'H'), fifo.readItem().?);
+        testing.expectEqual(@as(u8, 'E'), fifo.readItem().?);
+        testing.expectEqual(@as(u8, 'L'), fifo.readItem().?);
+        testing.expectEqual(@as(u8, 'L'), fifo.readItem().?);
+        testing.expectEqual(@as(u8, 'O'), fifo.readItem().?);
     }
     testing.expectEqual(@as(usize, 5), fifo.readableLength());
 
@@ -451,11 +454,11 @@ test "LinearFifo" {
             testing.expectEqual(@as(usize, 5), fifo.readableLength());
 
             {
-                testing.expectEqual(@as(T, 0), try fifo.readItem());
-                testing.expectEqual(@as(T, 1), try fifo.readItem());
-                testing.expectEqual(@as(T, 1), try fifo.readItem());
-                testing.expectEqual(@as(T, 0), try fifo.readItem());
-                testing.expectEqual(@as(T, 1), try fifo.readItem());
+                testing.expectEqual(@as(T, 0), fifo.readItem().?);
+                testing.expectEqual(@as(T, 1), fifo.readItem().?);
+                testing.expectEqual(@as(T, 1), fifo.readItem().?);
+                testing.expectEqual(@as(T, 0), fifo.readItem().?);
+                testing.expectEqual(@as(T, 1), fifo.readItem().?);
                 testing.expectEqual(@as(usize, 0), fifo.readableLength());
             }
 

lib/std/fs/file.zig

@@ -527,6 +527,33 @@ pub const File = struct {
         }
     }
 
+    pub const CopyRangeError = PWriteError || PReadError;
+
+    pub fn copyRange(in: File, in_offset: u64, out: File, out_offset: u64, len: usize) CopyRangeError!usize {
+        // TODO take advantage of copy_file_range OS APIs
+        var buf: [8 * 4096]u8 = undefined;
+        const adjusted_count = math.min(buf.len, len);
+        const amt_read = try in.pread(buf[0..adjusted_count], in_offset);
+        if (amt_read == 0) return @as(usize, 0);
+        return out.pwrite(buf[0..amt_read], out_offset);
+    }
+
+    /// Returns the number of bytes copied. If the number read is smaller than `buffer.len`, it
+    /// means the in file reached the end. Reaching the end of a file is not an error condition.
+    pub fn copyRangeAll(in: File, in_offset: u64, out: File, out_offset: u64, len: usize) CopyRangeError!usize {
+        var total_bytes_copied: usize = 0;
+        var in_off = in_offset;
+        var out_off = out_offset;
+        while (total_bytes_copied < len) {
+            const amt_copied = try copyRange(in, in_off, out, out_off, len - total_bytes_copied);
+            if (amt_copied == 0) return total_bytes_copied;
+            total_bytes_copied += amt_copied;
+            in_off += amt_copied;
+            out_off += amt_copied;
+        }
+        return total_bytes_copied;
+    }
+
     pub const WriteFileOptions = struct {
         in_offset: u64 = 0,
 

lib/std/hash_map.zig

@@ -10,7 +10,7 @@ const Wyhash = std.hash.Wyhash;
 const Allocator = mem.Allocator;
 const builtin = @import("builtin");
 
-const want_modification_safety = builtin.mode != .ReleaseFast;
+const want_modification_safety = std.debug.runtime_safety;
 const debug_u32 = if (want_modification_safety) u32 else void;
 
 pub fn AutoHashMap(comptime K: type, comptime V: type) type {
@@ -219,6 +219,10 @@ pub fn HashMap(comptime K: type, comptime V: type, comptime hash: fn (key: K) u3
             return put_result.old_kv;
         }
 
+        pub fn putAssumeCapacityNoClobber(self: *Self, key: K, value: V) void {
+            assert(self.putAssumeCapacity(key, value) == null);
+        }
+
         pub fn get(hm: *const Self, key: K) ?*KV {
             if (hm.entries.len == 0) {
                 return null;

lib/std/heap.zig

@@ -11,6 +11,7 @@ const maxInt = std.math.maxInt;
 
 pub const LoggingAllocator = @import("heap/logging_allocator.zig").LoggingAllocator;
 pub const loggingAllocator = @import("heap/logging_allocator.zig").loggingAllocator;
+pub const ArenaAllocator = @import("heap/arena_allocator.zig").ArenaAllocator;
 
 const Allocator = mem.Allocator;
 
@@ -510,95 +511,6 @@ pub const HeapAllocator = switch (builtin.os.tag) {
     else => @compileError("Unsupported OS"),
 };
 
-/// This allocator takes an existing allocator, wraps it, and provides an interface
-/// where you can allocate without freeing, and then free it all together.
-pub const ArenaAllocator = struct {
-    allocator: Allocator,
-
-    child_allocator: *Allocator,
-    buffer_list: std.SinglyLinkedList([]u8),
-    end_index: usize,
-
-    const BufNode = std.SinglyLinkedList([]u8).Node;
-
-    pub fn init(child_allocator: *Allocator) ArenaAllocator {
-        return ArenaAllocator{
-            .allocator = Allocator{
-                .reallocFn = realloc,
-                .shrinkFn = shrink,
-            },
-            .child_allocator = child_allocator,
-            .buffer_list = std.SinglyLinkedList([]u8).init(),
-            .end_index = 0,
-        };
-    }
-
-    pub fn deinit(self: ArenaAllocator) void {
-        var it = self.buffer_list.first;
-        while (it) |node| {
-            // this has to occur before the free because the free frees node
-            const next_it = node.next;
-            self.child_allocator.free(node.data);
-            it = next_it;
-        }
-    }
-
-    fn createNode(self: *ArenaAllocator, prev_len: usize, minimum_size: usize) !*BufNode {
-        const actual_min_size = minimum_size + @sizeOf(BufNode);
-        var len = prev_len;
-        while (true) {
-            len += len / 2;
-            len += mem.page_size - @rem(len, mem.page_size);
-            if (len >= actual_min_size) break;
-        }
-        const buf = try self.child_allocator.alignedAlloc(u8, @alignOf(BufNode), len);
-        const buf_node_slice = mem.bytesAsSlice(BufNode, buf[0..@sizeOf(BufNode)]);
-        const buf_node = &buf_node_slice[0];
-        buf_node.* = BufNode{
-            .data = buf,
-            .next = null,
-        };
-        self.buffer_list.prepend(buf_node);
-        self.end_index = 0;
-        return buf_node;
-    }
-
-    fn alloc(allocator: *Allocator, n: usize, alignment: u29) ![]u8 {
-        const self = @fieldParentPtr(ArenaAllocator, "allocator", allocator);
-
-        var cur_node = if (self.buffer_list.first) |first_node| first_node else try self.createNode(0, n + alignment);
-        while (true) {
-            const cur_buf = cur_node.data[@sizeOf(BufNode)..];
-            const addr = @ptrToInt(cur_buf.ptr) + self.end_index;
-            const adjusted_addr = mem.alignForward(addr, alignment);
-            const adjusted_index = self.end_index + (adjusted_addr - addr);
-            const new_end_index = adjusted_index + n;
-            if (new_end_index > cur_buf.len) {
-                cur_node = try self.createNode(cur_buf.len, n + alignment);
-                continue;
-            }
-            const result = cur_buf[adjusted_index..new_end_index];
-            self.end_index = new_end_index;
-            return result;
-        }
-    }
-
-    fn realloc(allocator: *Allocator, old_mem: []u8, old_align: u29, new_size: usize, new_align: u29) ![]u8 {
-        if (new_size <= old_mem.len and new_align <= new_size) {
-            // We can't do anything with the memory, so tell the client to keep it.
-            return error.OutOfMemory;
-        } else {
-            const result = try alloc(allocator, new_size, new_align);
-            @memcpy(result.ptr, old_mem.ptr, std.math.min(old_mem.len, result.len));
-            return result;
-        }
-    }
-
-    fn shrink(allocator: *Allocator, old_mem: []u8, old_align: u29, new_size: usize, new_align: u29) []u8 {
-        return old_mem[0..new_size];
-    }
-};
-
 pub const FixedBufferAllocator = struct {
     allocator: Allocator,
     end_index: usize,

lib/std/heap/arena_allocator.zig

@@ -0,0 +1,102 @@
+const std = @import("../std.zig");
+const assert = std.debug.assert;
+const mem = std.mem;
+const Allocator = std.mem.Allocator;
+
+/// This allocator takes an existing allocator, wraps it, and provides an interface
+/// where you can allocate without freeing, and then free it all together.
+pub const ArenaAllocator = struct {
+    allocator: Allocator,
+
+    child_allocator: *Allocator,
+    state: State,
+
+    /// Inner state of ArenaAllocator. Can be stored rather than the entire ArenaAllocator
+    /// as a memory-saving optimization.
+    pub const State = struct {
+        buffer_list: std.SinglyLinkedList([]u8) = @as(std.SinglyLinkedList([]u8), .{}),
+        end_index: usize = 0,
+
+        pub fn promote(self: State, child_allocator: *Allocator) ArenaAllocator {
+            return .{
+                .allocator = Allocator{
+                    .reallocFn = realloc,
+                    .shrinkFn = shrink,
+                },
+                .child_allocator = child_allocator,
+                .state = self,
+            };
+        }
+    };
+
+    const BufNode = std.SinglyLinkedList([]u8).Node;
+
+    pub fn init(child_allocator: *Allocator) ArenaAllocator {
+        return (State{}).promote(child_allocator);
+    }
+
+    pub fn deinit(self: ArenaAllocator) void {
+        var it = self.state.buffer_list.first;
+        while (it) |node| {
+            // this has to occur before the free because the free frees node
+            const next_it = node.next;
+            self.child_allocator.free(node.data);
+            it = next_it;
+        }
+    }
+
+    fn createNode(self: *ArenaAllocator, prev_len: usize, minimum_size: usize) !*BufNode {
+        const actual_min_size = minimum_size + @sizeOf(BufNode);
+        var len = prev_len;
+        while (true) {
+            len += len / 2;
+            len += mem.page_size - @rem(len, mem.page_size);
+            if (len >= actual_min_size) break;
+        }
+        const buf = try self.child_allocator.alignedAlloc(u8, @alignOf(BufNode), len);
+        const buf_node_slice = mem.bytesAsSlice(BufNode, buf[0..@sizeOf(BufNode)]);
+        const buf_node = &buf_node_slice[0];
+        buf_node.* = BufNode{
+            .data = buf,
+            .next = null,
+        };
+        self.state.buffer_list.prepend(buf_node);
+        self.state.end_index = 0;
+        return buf_node;
+    }
+
+    fn alloc(allocator: *Allocator, n: usize, alignment: u29) ![]u8 {
+        const self = @fieldParentPtr(ArenaAllocator, "allocator", allocator);
+
+        var cur_node = if (self.state.buffer_list.first) |first_node| first_node else try self.createNode(0, n + alignment);
+        while (true) {
+            const cur_buf = cur_node.data[@sizeOf(BufNode)..];
+            const addr = @ptrToInt(cur_buf.ptr) + self.state.end_index;
+            const adjusted_addr = mem.alignForward(addr, alignment);
+            const adjusted_index = self.state.end_index + (adjusted_addr - addr);
+            const new_end_index = adjusted_index + n;
+            if (new_end_index > cur_buf.len) {
+                cur_node = try self.createNode(cur_buf.len, n + alignment);
+                continue;
+            }
+            const result = cur_buf[adjusted_index..new_end_index];
+            self.state.end_index = new_end_index;
+            return result;
+        }
+    }
+
+    fn realloc(allocator: *Allocator, old_mem: []u8, old_align: u29, new_size: usize, new_align: u29) ![]u8 {
+        if (new_size <= old_mem.len and new_align <= new_size) {
+            // We can't do anything with the memory, so tell the client to keep it.
+            return error.OutOfMemory;
+        } else {
+            const result = try alloc(allocator, new_size, new_align);
+            @memcpy(result.ptr, old_mem.ptr, std.math.min(old_mem.len, result.len));
+            return result;
+        }
+    }
+
+    fn shrink(allocator: *Allocator, old_mem: []u8, old_align: u29, new_size: usize, new_align: u29) []u8 {
+        return old_mem[0..new_size];
+    }
+};

lib/std/linked_list.zig

@@ -49,7 +49,7 @@ pub fn SinglyLinkedList(comptime T: type) type {
             }
         };
 
-        first: ?*Node,
+        first: ?*Node = null,
 
         /// Initialize a linked list.
         ///

lib/std/mem.zig

@@ -279,6 +279,21 @@ pub const Allocator = struct {
         const shrink_result = self.shrinkFn(self, non_const_ptr[0..bytes_len], Slice.alignment, 0, 1);
         assert(shrink_result.len == 0);
     }
+
+    /// Copies `m` to newly allocated memory. Caller owns the memory.
+    pub fn dupe(allocator: *Allocator, comptime T: type, m: []const T) ![]T {
+        const new_buf = try allocator.alloc(T, m.len);
+        copy(T, new_buf, m);
+        return new_buf;
+    }
+
+    /// Copies `m` to newly allocated memory, with a null-terminated element. Caller owns the memory.
+    pub fn dupeZ(allocator: *Allocator, comptime T: type, m: []const T) ![:0]T {
+        const new_buf = try allocator.alloc(T, m.len + 1);
+        copy(T, new_buf, m);
+        new_buf[m.len] = 0;
+        return new_buf[0..m.len :0];
+    }
 };
 
 var failAllocator = Allocator {
@@ -785,19 +800,14 @@ pub fn allEqual(comptime T: type, slice: []const T, scalar: T) bool {
     return true;
 }
 
-/// Copies `m` to newly allocated memory. Caller owns the memory.
+/// Deprecated, use `Allocator.dupe`.
 pub fn dupe(allocator: *Allocator, comptime T: type, m: []const T) ![]T {
-    const new_buf = try allocator.alloc(T, m.len);
-    copy(T, new_buf, m);
-    return new_buf;
+    return allocator.dupe(T, m);
 }
 
-/// Copies `m` to newly allocated memory, with a null-terminated element. Caller owns the memory.
+/// Deprecated, use `Allocator.dupeZ`.
 pub fn dupeZ(allocator: *Allocator, comptime T: type, m: []const T) ![:0]T {
-    const new_buf = try allocator.alloc(T, m.len + 1);
-    copy(T, new_buf, m);
-    new_buf[m.len] = 0;
-    return new_buf[0..m.len :0];
+    return allocator.dupeZ(T, m);
 }
 
 /// Remove values from the beginning of a slice.
@@ -2112,7 +2122,11 @@ pub fn alignBackwardGeneric(comptime T: type, addr: T, alignment: T) T {
 /// Given an address and an alignment, return true if the address is a multiple of the alignment
 /// The alignment must be a power of 2 and greater than 0.
 pub fn isAligned(addr: usize, alignment: usize) bool {
-    return alignBackward(addr, alignment) == addr;
+    return isAlignedGeneric(u64, addr, alignment);
+}
+
+pub fn isAlignedGeneric(comptime T: type, addr: T, alignment: T) bool {
+    return alignBackwardGeneric(T, addr, alignment) == addr;
 }
 
 test "isAligned" {

lib/std/std.zig

@@ -1,6 +1,8 @@
-pub const AlignedArrayList = @import("array_list.zig").AlignedArrayList;
 pub const ArrayList = @import("array_list.zig").ArrayList;
+pub const ArrayListAligned = @import("array_list.zig").ArrayListAligned;
+pub const ArrayListAlignedUnmanaged = @import("array_list.zig").ArrayListAlignedUnmanaged;
 pub const ArrayListSentineled = @import("array_list_sentineled.zig").ArrayListSentineled;
+pub const ArrayListUnmanaged = @import("array_list.zig").ArrayListUnmanaged;
 pub const AutoHashMap = @import("hash_map.zig").AutoHashMap;
 pub const BloomFilter = @import("bloom_filter.zig").BloomFilter;
 pub const BufMap = @import("buf_map.zig").BufMap;

src-self-hosted/Package.zig

@@ -0,0 +1,53 @@
+pub const Table = std.StringHashMap(*Package);
+
+root_src_dir: std.fs.Dir,
+/// Relative to `root_src_dir`.
+root_src_path: []const u8,
+table: Table,
+
+/// No references to `root_src_dir` and `root_src_path` are kept.
+pub fn create(
+    allocator: *mem.Allocator,
+    base_dir: std.fs.Dir,
+    /// Relative to `base_dir`.
+    root_src_dir: []const u8,
+    /// Relative to `root_src_dir`.
+    root_src_path: []const u8,
+) !*Package {
+    const ptr = try allocator.create(Package);
+    errdefer allocator.destroy(ptr);
+    const root_src_path_dupe = try mem.dupe(allocator, u8, root_src_path);
+    errdefer allocator.free(root_src_path_dupe);
+    ptr.* = .{
+        .root_src_dir = try base_dir.openDir(root_src_dir, .{}),
+        .root_src_path = root_src_path_dupe,
+        .table = Table.init(allocator),
+    };
+    return ptr;
+}
+
+pub fn destroy(self: *Package) void {
+    const allocator = self.table.allocator;
+    self.root_src_dir.close();
+    allocator.free(self.root_src_path);
+    {
+        var it = self.table.iterator();
+        while (it.next()) |kv| {
+            allocator.free(kv.key);
+        }
+    }
+    self.table.deinit();
+    allocator.destroy(self);
+}
+
+pub fn add(self: *Package, name: []const u8, package: *Package) !void {
+    const name_dupe = try mem.dupe(self.table.allocator, u8, name);
+    errdefer self.table.allocator.deinit(name_dupe);
+    const entry = try self.table.put(name_dupe, package);
+    assert(entry == null);
+}
+
+const std = @import("std");
+const mem = std.mem;
+const assert = std.debug.assert;
+const Package = @This();

src-self-hosted/TypedValue.zig

@@ -0,0 +1,23 @@
+const std = @import("std");
+const Type = @import("type.zig").Type;
+const Value = @import("value.zig").Value;
+const Allocator = std.mem.Allocator;
+const TypedValue = @This();
+
+ty: Type,
+val: Value,
+
+/// Memory management for TypedValue. The main purpose of this type
+/// is to be small and have a deinit() function to free associated resources.
+pub const Managed = struct {
+    /// If the tag value is less than Tag.no_payload_count, then no pointer
+    /// dereference is needed.
+    typed_value: TypedValue,
+    /// If this is `null` then there is no memory management needed.
+    arena: ?*std.heap.ArenaAllocator.State = null,
+
+    pub fn deinit(self: *Managed, allocator: *Allocator) void {
+        if (self.arena) |a| a.promote(allocator).deinit();
+        self.* = undefined;
+    }
+};

src-self-hosted/c.zig

@@ -1,7 +0,0 @@
-pub usingnamespace @cImport({
-    @cDefine("__STDC_CONSTANT_MACROS", "");
-    @cDefine("__STDC_LIMIT_MACROS", "");
-    @cInclude("inttypes.h");
-    @cInclude("config.h");
-    @cInclude("zig_llvm.h");
-});

src-self-hosted/codegen.zig

@@ -4,64 +4,155 @@ const assert = std.debug.assert;
 const ir = @import("ir.zig");
 const Type = @import("type.zig").Type;
 const Value = @import("value.zig").Value;
+const TypedValue = @import("TypedValue.zig");
+const link = @import("link.zig");
+const Module = @import("Module.zig");
+const ErrorMsg = Module.ErrorMsg;
 const Target = std.Target;
+const Allocator = mem.Allocator;
 
-pub const ErrorMsg = struct {
-    byte_offset: usize,
-    msg: []const u8,
+pub const Result = union(enum) {
+    /// The `code` parameter passed to `generateSymbol` has the value appended.
+    appended: void,
+    /// The value is available externally, `code` is unused.
+    externally_managed: []const u8,
+    fail: *Module.ErrorMsg,
 };
 
-pub const Symbol = struct {
-    errors: []ErrorMsg,
-
-    pub fn deinit(self: *Symbol, allocator: *mem.Allocator) void {
-        for (self.errors) |err| {
-            allocator.free(err.msg);
-        }
-        allocator.free(self.errors);
-        self.* = undefined;
-    }
-};
-
-pub fn generateSymbol(typed_value: ir.TypedValue, module: ir.Module, code: *std.ArrayList(u8)) !Symbol {
+pub fn generateSymbol(
+    bin_file: *link.ElfFile,
+    src: usize,
+    typed_value: TypedValue,
+    code: *std.ArrayList(u8),
+) error{
+    OutOfMemory,
+    /// A Decl that this symbol depends on had a semantic analysis failure.
+    AnalysisFail,
+}!Result {
     switch (typed_value.ty.zigTypeTag()) {
         .Fn => {
-            const index = typed_value.val.cast(Value.Payload.Function).?.index;
-            const module_fn = module.fns[index];
+            const module_fn = typed_value.val.cast(Value.Payload.Function).?.func;
 
             var function = Function{
-                .module = &module,
-                .mod_fn = &module_fn,
+                .target = &bin_file.options.target,
+                .bin_file = bin_file,
+                .mod_fn = module_fn,
                 .code = code,
-                .inst_table = std.AutoHashMap(*ir.Inst, Function.MCValue).init(code.allocator),
-                .errors = std.ArrayList(ErrorMsg).init(code.allocator),
+                .inst_table = std.AutoHashMap(*ir.Inst, Function.MCValue).init(bin_file.allocator),
+                .err_msg = null,
             };
             defer function.inst_table.deinit();
-            defer function.errors.deinit();
 
-            for (module_fn.body.instructions) |inst| {
+            for (module_fn.analysis.success.instructions) |inst| {
                 const new_inst = function.genFuncInst(inst) catch |err| switch (err) {
-                    error.CodegenFail => {
-                        assert(function.errors.items.len != 0);
-                        break;
-                    },
+                    error.CodegenFail => return Result{ .fail = function.err_msg.? },
                     else => |e| return e,
                 };
                 try function.inst_table.putNoClobber(inst, new_inst);
             }
 
-            return Symbol{ .errors = function.errors.toOwnedSlice() };
+            if (function.err_msg) |em| {
+                return Result{ .fail = em };
+            } else {
+                return Result{ .appended = {} };
+            }
+        },
+        .Array => {
+            if (typed_value.val.cast(Value.Payload.Bytes)) |payload| {
+                if (typed_value.ty.arraySentinel()) |sentinel| {
+                    try code.ensureCapacity(code.items.len + payload.data.len + 1);
+                    code.appendSliceAssumeCapacity(payload.data);
+                    const prev_len = code.items.len;
+                    switch (try generateSymbol(bin_file, src, .{
+                        .ty = typed_value.ty.elemType(),
+                        .val = sentinel,
+                    }, code)) {
+                        .appended => return Result{ .appended = {} },
+                        .externally_managed => |slice| {
+                            code.appendSliceAssumeCapacity(slice);
+                            return Result{ .appended = {} };
+                        },
+                        .fail => |em| return Result{ .fail = em },
+                    }
+                } else {
+                    return Result{ .externally_managed = payload.data };
+                }
+            }
+            return Result{
+                .fail = try ErrorMsg.create(
+                    bin_file.allocator,
+                    src,
+                    "TODO implement generateSymbol for more kinds of arrays",
+                    .{},
+                ),
+            };
+        },
+        .Pointer => {
+            if (typed_value.val.cast(Value.Payload.DeclRef)) |payload| {
+                const decl = payload.decl;
+                if (decl.analysis != .complete) return error.AnalysisFail;
+                assert(decl.link.local_sym_index != 0);
+                // TODO handle the dependency of this symbol on the decl's vaddr.
+                // If the decl changes vaddr, then this symbol needs to get regenerated.
+                const vaddr = bin_file.local_symbols.items[decl.link.local_sym_index].st_value;
+                const endian = bin_file.options.target.cpu.arch.endian();
+                switch (bin_file.ptr_width) {
+                    .p32 => {
+                        try code.resize(4);
+                        mem.writeInt(u32, code.items[0..4], @intCast(u32, vaddr), endian);
+                    },
+                    .p64 => {
+                        try code.resize(8);
+                        mem.writeInt(u64, code.items[0..8], vaddr, endian);
+                    },
+                }
+                return Result{ .appended = {} };
+            }
+            return Result{
+                .fail = try ErrorMsg.create(
+                    bin_file.allocator,
+                    src,
+                    "TODO implement generateSymbol for pointer {}",
+                    .{typed_value.val},
+                ),
+            };
+        },
+        .Int => {
+            const info = typed_value.ty.intInfo(bin_file.options.target);
+            if (info.bits == 8 and !info.signed) {
+                const x = typed_value.val.toUnsignedInt();
+                try code.append(@intCast(u8, x));
+                return Result{ .appended = {} };
+            }
+            return Result{
+                .fail = try ErrorMsg.create(
+                    bin_file.allocator,
+                    src,
+                    "TODO implement generateSymbol for int type '{}'",
+                    .{typed_value.ty},
+                ),
+            };
+        },
+        else => |t| {
+            return Result{
+                .fail = try ErrorMsg.create(
+                    bin_file.allocator,
+                    src,
+                    "TODO implement generateSymbol for type '{}'",
+                    .{@tagName(t)},
+                ),
+            };
         },
-        else => @panic("TODO implement generateSymbol for non-function types"),
     }
 }
 
 const Function = struct {
-    module: *const ir.Module,
-    mod_fn: *const ir.Module.Fn,
+    bin_file: *link.ElfFile,
+    target: *const std.Target,
+    mod_fn: *const Module.Fn,
     code: *std.ArrayList(u8),
     inst_table: std.AutoHashMap(*ir.Inst, MCValue),
-    errors: std.ArrayList(ErrorMsg),
+    err_msg: ?*ErrorMsg,
 
     const MCValue = union(enum) {
         none,
@@ -73,11 +164,14 @@ const Function = struct {
         /// The value is in a target-specific register. The value can
         /// be @intToEnum casted to the respective Reg enum.
         register: usize,
+        /// The value is in memory at a hard-coded address.
+        memory: u64,
     };
 
     fn genFuncInst(self: *Function, inst: *ir.Inst) !MCValue {
         switch (inst.tag) {
             .breakpoint => return self.genBreakpoint(inst.src),
+            .call => return self.genCall(inst.cast(ir.Inst.Call).?),
             .unreach => return MCValue{ .unreach = {} },
             .constant => unreachable, // excluded from function bodies
             .assembly => return self.genAsm(inst.cast(ir.Inst.Assembly).?),
@@ -92,54 +186,76 @@ const Function = struct {
     }
 
     fn genBreakpoint(self: *Function, src: usize) !MCValue {
-        switch (self.module.target.cpu.arch) {
+        switch (self.target.cpu.arch) {
             .i386, .x86_64 => {
                 try self.code.append(0xcc); // int3
             },
-            else => return self.fail(src, "TODO implement @breakpoint() for {}", .{self.module.target.cpu.arch}),
+            else => return self.fail(src, "TODO implement @breakpoint() for {}", .{self.target.cpu.arch}),
+        }
+        return .none;
+    }
+
+    fn genCall(self: *Function, inst: *ir.Inst.Call) !MCValue {
+        if (inst.args.func.cast(ir.Inst.Constant)) |func_inst| {
+            if (inst.args.args.len != 0) {
+                return self.fail(inst.base.src, "TODO implement call with more than 0 parameters", .{});
+            }
+
+            if (func_inst.val.cast(Value.Payload.Function)) |func_val| {
+                const func = func_val.func;
+                return self.fail(inst.base.src, "TODO implement calling function", .{});
+            } else {
+                return self.fail(inst.base.src, "TODO implement calling weird function values", .{});
+            }
+        } else {
+            return self.fail(inst.base.src, "TODO implement calling runtime known function pointer", .{});
+        }
+
+        switch (self.target.cpu.arch) {
+            else => return self.fail(inst.base.src, "TODO implement call for {}", .{self.target.cpu.arch}),
         }
-        return .unreach;
     }
 
     fn genRet(self: *Function, inst: *ir.Inst.Ret) !MCValue {
-        switch (self.module.target.cpu.arch) {
+        switch (self.target.cpu.arch) {
             .i386, .x86_64 => {
                 try self.code.append(0xc3); // ret
             },
-            else => return self.fail(inst.base.src, "TODO implement return for {}", .{self.module.target.cpu.arch}),
+            else => return self.fail(inst.base.src, "TODO implement return for {}", .{self.target.cpu.arch}),
         }
         return .unreach;
     }
 
     fn genCmp(self: *Function, inst: *ir.Inst.Cmp) !MCValue {
-        switch (self.module.target.cpu.arch) {
-            else => return self.fail(inst.base.src, "TODO implement cmp for {}", .{self.module.target.cpu.arch}),
+        switch (self.target.cpu.arch) {
+            else => return self.fail(inst.base.src, "TODO implement cmp for {}", .{self.target.cpu.arch}),
         }
     }
 
     fn genCondBr(self: *Function, inst: *ir.Inst.CondBr) !MCValue {
-        switch (self.module.target.cpu.arch) {
-            else => return self.fail(inst.base.src, "TODO implement condbr for {}", .{self.module.target.cpu.arch}),
+        switch (self.target.cpu.arch) {
+            else => return self.fail(inst.base.src, "TODO implement condbr for {}", .{self.target.cpu.arch}),
         }
     }
 
     fn genIsNull(self: *Function, inst: *ir.Inst.IsNull) !MCValue {
-        switch (self.module.target.cpu.arch) {
-            else => return self.fail(inst.base.src, "TODO implement isnull for {}", .{self.module.target.cpu.arch}),
+        switch (self.target.cpu.arch) {
+            else => return self.fail(inst.base.src, "TODO implement isnull for {}", .{self.target.cpu.arch}),
         }
     }
 
     fn genIsNonNull(self: *Function, inst: *ir.Inst.IsNonNull) !MCValue {
         // Here you can specialize this instruction if it makes sense to, otherwise the default
         // will call genIsNull and invert the result.
-        switch (self.module.target.cpu.arch) {
+        switch (self.target.cpu.arch) {
             else => return self.fail(inst.base.src, "TODO call genIsNull and invert the result ", .{}),
         }
     }
 
     fn genRelativeFwdJump(self: *Function, src: usize, amount: u32) !void {
-        switch (self.module.target.cpu.arch) {
+        switch (self.target.cpu.arch) {
             .i386, .x86_64 => {
+                // TODO x86 treats the operands as signed
                 if (amount <= std.math.maxInt(u8)) {
                     try self.code.resize(self.code.items.len + 2);
                     self.code.items[self.code.items.len - 2] = 0xeb;
@@ -151,13 +267,13 @@ const Function = struct {
                     mem.writeIntLittle(u32, imm_ptr, amount);
                 }
             },
-            else => return self.fail(src, "TODO implement relative forward jump for {}", .{self.module.target.cpu.arch}),
+            else => return self.fail(src, "TODO implement relative forward jump for {}", .{self.target.cpu.arch}),
         }
     }
 
     fn genAsm(self: *Function, inst: *ir.Inst.Assembly) !MCValue {
         // TODO convert to inline function
-        switch (self.module.target.cpu.arch) {
+        switch (self.target.cpu.arch) {
             .arm => return self.genAsmArch(.arm, inst),
             .armeb => return self.genAsmArch(.armeb, inst),
             .aarch64 => return self.genAsmArch(.aarch64, inst),
@@ -246,128 +362,182 @@ const Function = struct {
         }
     }
 
-    fn genSetReg(self: *Function, src: usize, comptime arch: Target.Cpu.Arch, reg: Reg(arch), mcv: MCValue) !void {
+    fn genSetReg(self: *Function, src: usize, comptime arch: Target.Cpu.Arch, reg: Reg(arch), mcv: MCValue) error{ CodegenFail, OutOfMemory }!void {
         switch (arch) {
-            .x86_64 => switch (reg) {
-                .rax => switch (mcv) {
-                    .none, .unreach => unreachable,
-                    .immediate => |x| {
-                        // Setting the eax register zeroes the upper part of rax, so if the number is small
-                        // enough, that is preferable.
-                        // Best case: zero
-                        // 31 c0     xor    eax,eax
-                        if (x == 0) {
-                            return self.code.appendSlice(&[_]u8{ 0x31, 0xc0 });
-                        }
-                        // Next best case: set eax with 4 bytes
-                        // b8 04 03 02 01           mov    eax,0x01020304
-                        if (x <= std.math.maxInt(u32)) {
-                            try self.code.resize(self.code.items.len + 5);
-                            self.code.items[self.code.items.len - 5] = 0xb8;
-                            const imm_ptr = self.code.items[self.code.items.len - 4 ..][0..4];
-                            mem.writeIntLittle(u32, imm_ptr, @intCast(u32, x));
-                            return;
-                        }
-                        // Worst case: set rax with 8 bytes
-                        // 48 b8 08 07 06 05 04 03 02 01    movabs rax,0x0102030405060708
-                        try self.code.resize(self.code.items.len + 10);
-                        self.code.items[self.code.items.len - 10] = 0x48;
-                        self.code.items[self.code.items.len - 9] = 0xb8;
-                        const imm_ptr = self.code.items[self.code.items.len - 8 ..][0..8];
-                        mem.writeIntLittle(u64, imm_ptr, x);
-                        return;
-                    },
-                    .embedded_in_code => return self.fail(src, "TODO implement x86_64 genSetReg %rax = embedded_in_code", .{}),
-                    .register => return self.fail(src, "TODO implement x86_64 genSetReg %rax = register", .{}),
-                },
-                .rdx => switch (mcv) {
-                    .none, .unreach => unreachable,
-                    .immediate => |x| {
-                        // Setting the edx register zeroes the upper part of rdx, so if the number is small
-                        // enough, that is preferable.
-                        // Best case: zero
-                        // 31 d2                    xor    edx,edx
-                        if (x == 0) {
-                            return self.code.appendSlice(&[_]u8{ 0x31, 0xd2 });
-                        }
-                        // Next best case: set edx with 4 bytes
-                        // ba 04 03 02 01           mov    edx,0x1020304
-                        if (x <= std.math.maxInt(u32)) {
-                            try self.code.resize(self.code.items.len + 5);
-                            self.code.items[self.code.items.len - 5] = 0xba;
-                            const imm_ptr = self.code.items[self.code.items.len - 4 ..][0..4];
-                            mem.writeIntLittle(u32, imm_ptr, @intCast(u32, x));
-                            return;
-                        }
-                        // Worst case: set rdx with 8 bytes
-                        // 48 ba 08 07 06 05 04 03 02 01    movabs rdx,0x0102030405060708
-                        try self.code.resize(self.code.items.len + 10);
-                        self.code.items[self.code.items.len - 10] = 0x48;
-                        self.code.items[self.code.items.len - 9] = 0xba;
-                        const imm_ptr = self.code.items[self.code.items.len - 8 ..][0..8];
-                        mem.writeIntLittle(u64, imm_ptr, x);
-                        return;
-                    },
-                    .embedded_in_code => return self.fail(src, "TODO implement x86_64 genSetReg %rdx = embedded_in_code", .{}),
-                    .register => return self.fail(src, "TODO implement x86_64 genSetReg %rdx = register", .{}),
-                },
-                .rdi => switch (mcv) {
-                    .none, .unreach => unreachable,
-                    .immediate => |x| {
-                        // Setting the edi register zeroes the upper part of rdi, so if the number is small
-                        // enough, that is preferable.
-                        // Best case: zero
-                        // 31 ff                    xor    edi,edi
-                        if (x == 0) {
-                            return self.code.appendSlice(&[_]u8{ 0x31, 0xff });
-                        }
-                        // Next best case: set edi with 4 bytes
-                        // bf 04 03 02 01           mov    edi,0x1020304
-                        if (x <= std.math.maxInt(u32)) {
-                            try self.code.resize(self.code.items.len + 5);
-                            self.code.items[self.code.items.len - 5] = 0xbf;
-                            const imm_ptr = self.code.items[self.code.items.len - 4 ..][0..4];
-                            mem.writeIntLittle(u32, imm_ptr, @intCast(u32, x));
-                            return;
-                        }
-                        // Worst case: set rdi with 8 bytes
-                        // 48 bf 08 07 06 05 04 03 02 01    movabs rax,0x0102030405060708
-                        try self.code.resize(self.code.items.len + 10);
-                        self.code.items[self.code.items.len - 10] = 0x48;
-                        self.code.items[self.code.items.len - 9] = 0xbf;
-                        const imm_ptr = self.code.items[self.code.items.len - 8 ..][0..8];
-                        mem.writeIntLittle(u64, imm_ptr, x);
-                        return;
-                    },
-                    .embedded_in_code => return self.fail(src, "TODO implement x86_64 genSetReg %rdi = embedded_in_code", .{}),
-                    .register => return self.fail(src, "TODO implement x86_64 genSetReg %rdi = register", .{}),
-                },
-                .rsi => switch (mcv) {
-                    .none, .unreach => unreachable,
-                    .immediate => return self.fail(src, "TODO implement x86_64 genSetReg %rsi = immediate", .{}),
-                    .embedded_in_code => |code_offset| {
-                        // Examples:
-                        // lea rsi, [rip + 0x01020304]
-                        // lea rsi, [rip - 7]
-                        //  f: 48 8d 35 04 03 02 01  lea    rsi,[rip+0x1020304]        # 102031a <_start+0x102031a>
-                        // 16: 48 8d 35 f9 ff ff ff  lea    rsi,[rip+0xfffffffffffffff9]        # 16 <_start+0x16>
+            .x86_64 => switch (mcv) {
+                .none, .unreach => unreachable,
+                .immediate => |x| {
+                    if (reg.size() != 64) {
+                        return self.fail(src, "TODO decide whether to implement non-64-bit loads", .{});
+                    }
+                    // 32-bit moves zero-extend to 64-bit, so xoring the 32-bit
+                    // register is the fastest way to zero a register.
+                    if (x == 0) {
+                        // The encoding for `xor r32, r32` is `0x31 /r`.
+                        // Section 3.1.1.1 of the Intel x64 Manual states that "/r indicates that the
+                        // ModR/M byte of the instruction contains a register operand and an r/m operand."
                         //
-                        // We need the offset from RIP in a signed i32 twos complement.
-                        // The instruction is 7 bytes long and RIP points to the next instruction.
-                        try self.code.resize(self.code.items.len + 7);
-                        const rip = self.code.items.len;
-                        const big_offset = @intCast(i64, code_offset) - @intCast(i64, rip);
-                        const offset = @intCast(i32, big_offset);
-                        self.code.items[self.code.items.len - 7] = 0x48;
-                        self.code.items[self.code.items.len - 6] = 0x8d;
-                        self.code.items[self.code.items.len - 5] = 0x35;
+                        // R/M bytes are composed of two bits for the mode, then three bits for the register,
+                        // then three bits for the operand. Since we're zeroing a register, the two three-bit
+                        // values will be identical, and the mode is three (the raw register value).
+                        //
+                        if (reg.isExtended()) {
+                            // If we're accessing e.g. r8d, we need to use a REX prefix before the actual operation. Since
+                            // this is a 32-bit operation, the W flag is set to zero. X is also zero, as we're not using a SIB.
+                            // Both R and B are set, as we're extending, in effect, the register bits *and* the operand.
+                            //
+                            // From section 2.2.1.2 of the manual, REX is encoded as b0100WRXB. In this case, that's
+                            // b01000101, or 0x45.
+                            return self.code.appendSlice(&[_]u8{
+                                0x45,
+                                0x31,
+                                0xC0 | (@as(u8, reg.id() & 0b111) << 3) | @truncate(u3, reg.id()),
+                            });
+                        } else {
+                            return self.code.appendSlice(&[_]u8{
+                                0x31,
+                                0xC0 | (@as(u8, reg.id()) << 3) | reg.id(),
+                            });
+                        }
+                    }
+                    if (x <= std.math.maxInt(u32)) {
+                        // Next best case: if we set the lower four bytes, the upper four will be zeroed.
+                        //
+                        // The encoding for `mov IMM32 -> REG` is (0xB8 + R) IMM.
+                        if (reg.isExtended()) {
+                            // Just as with XORing, we need a REX prefix. This time though, we only
+                            // need the B bit set, as we're extending the opcode's register field,
+                            // and there is no Mod R/M byte.
+                            //
+                            // Thus, we need b01000001, or 0x41.
+                            try self.code.resize(self.code.items.len + 6);
+                            self.code.items[self.code.items.len - 6] = 0x41;
+                        } else {
+                            try self.code.resize(self.code.items.len + 5);
+                        }
+                        self.code.items[self.code.items.len - 5] = 0xB8 | @as(u8, reg.id() & 0b111);
                         const imm_ptr = self.code.items[self.code.items.len - 4 ..][0..4];
-                        mem.writeIntLittle(i32, imm_ptr, offset);
+                        mem.writeIntLittle(u32, imm_ptr, @intCast(u32, x));
                         return;
-                    },
-                    .register => return self.fail(src, "TODO implement x86_64 genSetReg %rsi = register", .{}),
+                    }
+                    // Worst case: we need to load the 64-bit register with the IMM. GNU's assemblers calls
+                    // this `movabs`, though this is officially just a different variant of the plain `mov`
+                    // instruction.
+                    //
+                    // This encoding is, in fact, the *same* as the one used for 32-bit loads. The only
+                    // difference is that we set REX.W before the instruction, which extends the load to
+                    // 64-bit and uses the full bit-width of the register.
+                    //
+                    // Since we always need a REX here, let's just check if we also need to set REX.B.
+                    //
+                    // In this case, the encoding of the REX byte is 0b0100100B
+                    const REX = 0x48 | (if (reg.isExtended()) @as(u8, 0x01) else 0);
+                    try self.code.resize(self.code.items.len + 10);
+                    self.code.items[self.code.items.len - 10] = REX;
+                    self.code.items[self.code.items.len - 9] = 0xB8 | @as(u8, reg.id() & 0b111);
+                    const imm_ptr = self.code.items[self.code.items.len - 8 ..][0..8];
+                    mem.writeIntLittle(u64, imm_ptr, x);
+                },
+                .embedded_in_code => |code_offset| {
+                    if (reg.size() != 64) {
+                        return self.fail(src, "TODO decide whether to implement non-64-bit loads", .{});
+                    }
+                    // We need the offset from RIP in a signed i32 twos complement.
+                    // The instruction is 7 bytes long and RIP points to the next instruction.
+                    //
+                    // 64-bit LEA is encoded as REX.W 8D /r. If the register is extended, the REX byte is modified,
+                    // but the operation size is unchanged. Since we're using a disp32, we want mode 0 and lower three
+                    // bits as five.
+                    // REX 0x8D 0b00RRR101, where RRR is the lower three bits of the id.
+                    try self.code.resize(self.code.items.len + 7);
+                    const REX = 0x48 | if (reg.isExtended()) @as(u8, 1) else 0;
+                    const rip = self.code.items.len;
+                    const big_offset = @intCast(i64, code_offset) - @intCast(i64, rip);
+                    const offset = @intCast(i32, big_offset);
+                    self.code.items[self.code.items.len - 7] = REX;
+                    self.code.items[self.code.items.len - 6] = 0x8D;
+                    self.code.items[self.code.items.len - 5] = 0b101 | (@as(u8, reg.id() & 0b111) << 3);
+                    const imm_ptr = self.code.items[self.code.items.len - 4 ..][0..4];
+                    mem.writeIntLittle(i32, imm_ptr, offset);
+                },
+                .register => |r| {
+                    if (reg.size() != 64) {
+                        return self.fail(src, "TODO decide whether to implement non-64-bit loads", .{});
+                    }
+                    const src_reg = @intToEnum(Reg(arch), @intCast(u8, r));
+                    // This is a varient of 8B /r. Since we're using 64-bit moves, we require a REX.
+                    // This is thus three bytes: REX 0x8B R/M.
+                    // If the destination is extended, the R field must be 1.
+                    // If the *source* is extended, the B field must be 1.
+                    // Since the register is being accessed directly, the R/M mode is three. The reg field (the middle
+                    // three bits) contain the destination, and the R/M field (the lower three bits) contain the source.
+                    const REX = 0x48 | (if (reg.isExtended()) @as(u8, 4) else 0) | (if (src_reg.isExtended()) @as(u8, 1) else 0);
+                    const R = 0xC0 | (@as(u8, reg.id() & 0b111) << 3) | @truncate(u3, src_reg.id());
+                    try self.code.appendSlice(&[_]u8{ REX, 0x8B, R });
+                },
+                .memory => |x| {
+                    if (reg.size() != 64) {
+                        return self.fail(src, "TODO decide whether to implement non-64-bit loads", .{});
+                    }
+                    if (x <= std.math.maxInt(u32)) {
+                        // Moving from memory to a register is a variant of `8B /r`.
+                        // Since we're using 64-bit moves, we require a REX.
+                        // This variant also requires a SIB, as it would otherwise be RIP-relative.
+                        // We want mode zero with the lower three bits set to four to indicate an SIB with no other displacement.
+                        // The SIB must be 0x25, to indicate a disp32 with no scaled index.
+                        // 0b00RRR100, where RRR is the lower three bits of the register ID.
+                        // The instruction is thus eight bytes; REX 0x8B 0b00RRR100 0x25 followed by a four-byte disp32.
+                        try self.code.resize(self.code.items.len + 8);
+                        const REX = 0x48 | if (reg.isExtended()) @as(u8, 1) else 0;
+                        const r = 0x04 | (@as(u8, reg.id() & 0b111) << 3);
+                        self.code.items[self.code.items.len - 8] = REX;
+                        self.code.items[self.code.items.len - 7] = 0x8B;
+                        self.code.items[self.code.items.len - 6] = r;
+                        self.code.items[self.code.items.len - 5] = 0x25;
+                        const imm_ptr = self.code.items[self.code.items.len - 4 ..][0..4];
+                        mem.writeIntLittle(u32, imm_ptr, @intCast(u32, x));
+                    } else {
+                        // If this is RAX, we can use a direct load; otherwise, we need to load the address, then indirectly load
+                        // the value.
+                        if (reg.id() == 0) {
+                            // REX.W 0xA1 moffs64*
+                            // moffs64* is a 64-bit offset "relative to segment base", which really just means the
+                            // absolute address for all practical purposes.
+                            try self.code.resize(self.code.items.len + 10);
+                            // REX.W == 0x48
+                            self.code.items[self.code.items.len - 10] = 0x48;
+                            self.code.items[self.code.items.len - 9] = 0xA1;
+                            const imm_ptr = self.code.items[self.code.items.len - 8 ..][0..8];
+                            mem.writeIntLittle(u64, imm_ptr, x);
+                        } else {
+                            // This requires two instructions; a move imm as used above, followed by an indirect load using the register
+                            // as the address and the register as the destination.
+                            //
+                            // This cannot be used if the lower three bits of the id are equal to four or five, as there
+                            // is no way to possibly encode it. This means that RSP, RBP, R12, and R13 cannot be used with
+                            // this instruction.
+                            const id3 = @truncate(u3, reg.id());
+                            std.debug.assert(id3 != 4 and id3 != 5);
+
+                            // Rather than duplicate the logic used for the move, we just use a self-call with a new MCValue.
+                            try self.genSetReg(src, arch, reg, MCValue{ .immediate = x });
+
+                            // Now, the register contains the address of the value to load into it
+                            // Currently, we're only allowing 64-bit registers, so we need the `REX.W 8B /r` variant.
+                            // TODO: determine whether to allow other sized registers, and if so, handle them properly.
+                            // This operation requires three bytes: REX 0x8B R/M
+                            //
+                            // For this operation, we want R/M mode *zero* (use register indirectly), and the two register
+                            // values must match. Thus, it's 00ABCABC where ABC is the lower three bits of the register ID.
+                            //
+                            // Furthermore, if this is an extended register, both B and R must be set in the REX byte, as *both*
+                            // register operands need to be marked as extended.
+                            const REX = 0x48 | if (reg.isExtended()) @as(u8, 0b0101) else 0;
+                            const RM = (@as(u8, reg.id() & 0b111) << 3) | @truncate(u3, reg.id());
+                            try self.code.appendSlice(&[_]u8{ REX, 0x8B, RM });
+                        }
+                    }
                 },
-                else => return self.fail(src, "TODO implement genSetReg for x86_64 '{}'", .{@tagName(reg)}),
             },
             else => return self.fail(src, "TODO implement genSetReg for more architectures", .{}),
         }
@@ -396,30 +566,22 @@ const Function = struct {
         }
     }
 
-    fn genTypedValue(self: *Function, src: usize, typed_value: ir.TypedValue) !MCValue {
+    fn genTypedValue(self: *Function, src: usize, typed_value: TypedValue) !MCValue {
+        const ptr_bits = self.target.cpu.arch.ptrBitWidth();
+        const ptr_bytes: u64 = @divExact(ptr_bits, 8);
+        const allocator = self.code.allocator;
         switch (typed_value.ty.zigTypeTag()) {
             .Pointer => {
-                const ptr_elem_type = typed_value.ty.elemType();
-                switch (ptr_elem_type.zigTypeTag()) {
-                    .Array => {
-                        // TODO more checks to make sure this can be emitted as a string literal
-                        const bytes = try typed_value.val.toAllocatedBytes(self.code.allocator);
-                        defer self.code.allocator.free(bytes);
-                        const smaller_len = std.math.cast(u32, bytes.len) catch
-                            return self.fail(src, "TODO handle a larger string constant", .{});
-
-                        // Emit the string literal directly into the code; jump over it.
-                        try self.genRelativeFwdJump(src, smaller_len);
-                        const offset = self.code.items.len;
-                        try self.code.appendSlice(bytes);
-                        return MCValue{ .embedded_in_code = offset };
-                    },
-                    else => |t| return self.fail(src, "TODO implement emitTypedValue for pointer to '{}'", .{@tagName(t)}),
+                if (typed_value.val.cast(Value.Payload.DeclRef)) |payload| {
+                    const got = &self.bin_file.program_headers.items[self.bin_file.phdr_got_index.?];
+                    const decl = payload.decl;
+                    const got_addr = got.p_vaddr + decl.link.offset_table_index * ptr_bytes;
+                    return MCValue{ .memory = got_addr };
                 }
+                return self.fail(src, "TODO codegen more kinds of const pointers", .{});
             },
             .Int => {
-                const info = typed_value.ty.intInfo(self.module.target);
-                const ptr_bits = self.module.target.cpu.arch.ptrBitWidth();
+                const info = typed_value.ty.intInfo(self.target.*);
                 if (info.bits > ptr_bits or info.signed) {
                     return self.fail(src, "TODO const int bigger than ptr and signed int", .{});
                 }
@@ -433,127 +595,19 @@ const Function = struct {
 
     fn fail(self: *Function, src: usize, comptime format: []const u8, args: var) error{ CodegenFail, OutOfMemory } {
         @setCold(true);
-        const msg = try std.fmt.allocPrint(self.errors.allocator, format, args);
-        {
-            errdefer self.errors.allocator.free(msg);
-            (try self.errors.addOne()).* = .{
-                .byte_offset = src,
-                .msg = msg,
-            };
-        }
+        assert(self.err_msg == null);
+        self.err_msg = try ErrorMsg.create(self.code.allocator, src, format, args);
         return error.CodegenFail;
     }
 };
 
+const x86_64 = @import("codegen/x86_64.zig");
+const x86 = @import("codegen/x86.zig");
+
 fn Reg(comptime arch: Target.Cpu.Arch) type {
     return switch (arch) {
-        .i386 => enum {
-            eax,
-            ebx,
-            ecx,
-            edx,
-            ebp,
-            esp,
-            esi,
-            edi,
-
-            ax,
-            bx,
-            cx,
-            dx,
-            bp,
-            sp,
-            si,
-            di,
-
-            ah,
-            bh,
-            ch,
-            dh,
-
-            al,
-            bl,
-            cl,
-            dl,
-        },
-        .x86_64 => enum {
-            rax,
-            rbx,
-            rcx,
-            rdx,
-            rbp,
-            rsp,
-            rsi,
-            rdi,
-            r8,
-            r9,
-            r10,
-            r11,
-            r12,
-            r13,
-            r14,
-            r15,
-
-            eax,
-            ebx,
-            ecx,
-            edx,
-            ebp,
-            esp,
-            esi,
-            edi,
-            r8d,
-            r9d,
-            r10d,
-            r11d,
-            r12d,
-            r13d,
-            r14d,
-            r15d,
-
-            ax,
-            bx,
-            cx,
-            dx,
-            bp,
-            sp,
-            si,
-            di,
-            r8w,
-            r9w,
-            r10w,
-            r11w,
-            r12w,
-            r13w,
-            r14w,
-            r15w,
-
-            ah,
-            bh,
-            ch,
-            dh,
-            bph,
-            sph,
-            sih,
-            dih,
-
-            al,
-            bl,
-            cl,
-            dl,
-            bpl,
-            spl,
-            sil,
-            dil,
-            r8b,
-            r9b,
-            r10b,
-            r11b,
-            r12b,
-            r13b,
-            r14b,
-            r15b,
-        },
+        .i386 => x86.Register,
+        .x86_64 => x86_64.Register,
         else => @compileError("TODO add more register enums"),
     };
 }

src-self-hosted/codegen/x86.zig

@@ -0,0 +1,30 @@
+// zig fmt: off
+pub const Register = enum(u8) {
+    // 0 through 7, 32-bit registers. id is int value
+    eax, ecx, edx, ebx, esp, ebp, esi, edi, 
+
+    // 8-15, 16-bit registers. id is int value - 8.
+    ax, cx, dx, bx, sp, bp, si, di,
+    
+    // 16-23, 8-bit registers. id is int value - 16.
+    al, bl, cl, dl, ah, ch, dh, bh,
+
+    /// Returns the bit-width of the register.
+    pub fn size(self: @This()) u7 {
+        return switch (@enumToInt(self)) {
+            0...7 => 32,
+            8...15 => 16,
+            16...23 => 8,
+            else => unreachable,
+        };
+    }
+
+    /// Returns the register's id. This is used in practically every opcode the
+    /// x86 has. It is embedded in some instructions, such as the `B8 +rd` move
+    /// instruction, and is used in the R/M byte.
+    pub fn id(self: @This()) u3 {
+        return @truncate(u3, @enumToInt(self));
+    }
+};
+
+// zig fmt: on

src-self-hosted/codegen/x86_64.zig

@@ -0,0 +1,53 @@
+// zig fmt: off
+pub const Register = enum(u8) {
+    // 0 through 15, 64-bit registers. 8-15 are extended.
+    // id is just the int value.
+    rax, rcx, rdx, rbx, rsp, rbp, rsi, rdi,
+    r8, r9, r10, r11, r12, r13, r14, r15,
+
+    // 16 through 31, 32-bit registers. 24-31 are extended.
+    // id is int value - 16.
+    eax, ecx, edx, ebx, esp, ebp, esi, edi, 
+    r8d, r9d, r10d, r11d, r12d, r13d, r14d, r15d,
+
+    // 32-47, 16-bit registers. 40-47 are extended.
+    // id is int value - 32.
+    ax, cx, dx, bx, sp, bp, si, di,
+    r8w, r9w, r10w, r11w, r12w, r13w, r14w, r15w,
+    
+    // 48-63, 8-bit registers. 56-63 are extended.
+    // id is int value - 48.
+    al, bl, cl, dl, ah, ch, dh, bh,
+    r8b, r9b, r10b, r11b, r12b, r13b, r14b, r15b,
+
+    /// Returns the bit-width of the register.
+    pub fn size(self: @This()) u7 {
+        return switch (@enumToInt(self)) {
+            0...15 => 64,
+            16...31 => 32,
+            32...47 => 16,
+            48...64 => 8,
+            else => unreachable,
+        };
+    }
+
+    /// Returns whether the register is *extended*. Extended registers are the
+    /// new registers added with amd64, r8 through r15. This also includes any
+    /// other variant of access to those registers, such as r8b, r15d, and so
+    /// on. This is needed because access to these registers requires special
+    /// handling via the REX prefix, via the B or R bits, depending on context.
+    pub fn isExtended(self: @This()) bool {
+        return @enumToInt(self) & 0x08 != 0;
+    }
+
+    /// This returns the 4-bit register ID, which is used in practically every
+    /// opcode. Note that bit 3 (the highest bit) is *never* used directly in
+    /// an instruction (@see isExtended), and requires special handling. The
+    /// lower three bits are often embedded directly in instructions (such as
+    /// the B8 variant of moves), or used in R/M bytes.
+    pub fn id(self: @This()) u4 {
+        return @truncate(u4, @enumToInt(self));
+    }
+};
+
+// zig fmt: on

src-self-hosted/decl.zig

@@ -1,102 +0,0 @@
-const std = @import("std");
-const Allocator = mem.Allocator;
-const mem = std.mem;
-const ast = std.zig.ast;
-const Visib = @import("visib.zig").Visib;
-const event = std.event;
-const Value = @import("value.zig").Value;
-const Token = std.zig.Token;
-const errmsg = @import("errmsg.zig");
-const Scope = @import("scope.zig").Scope;
-const Compilation = @import("compilation.zig").Compilation;
-
-pub const Decl = struct {
-    id: Id,
-    name: []const u8,
-    visib: Visib,
-    resolution: event.Future(Compilation.BuildError!void),
-    parent_scope: *Scope,
-
-    // TODO when we destroy the decl, deref the tree scope
-    tree_scope: *Scope.AstTree,
-
-    pub const Table = std.StringHashMap(*Decl);
-
-    pub fn cast(base: *Decl, comptime T: type) ?*T {
-        if (base.id != @field(Id, @typeName(T))) return null;
-        return @fieldParentPtr(T, "base", base);
-    }
-
-    pub fn isExported(base: *const Decl, tree: *ast.Tree) bool {
-        switch (base.id) {
-            .Fn => {
-                const fn_decl = @fieldParentPtr(Fn, "base", base);
-                return fn_decl.isExported(tree);
-            },
-            else => return false,
-        }
-    }
-
-    pub fn getSpan(base: *const Decl) errmsg.Span {
-        switch (base.id) {
-            .Fn => {
-                const fn_decl = @fieldParentPtr(Fn, "base", base);
-                const fn_proto = fn_decl.fn_proto;
-                const start = fn_proto.fn_token;
-                const end = fn_proto.name_token orelse start;
-                return errmsg.Span{
-                    .first = start,
-                    .last = end + 1,
-                };
-            },
-            else => @panic("TODO"),
-        }
-    }
-
-    pub fn findRootScope(base: *const Decl) *Scope.Root {
-        return base.parent_scope.findRoot();
-    }
-
-    pub const Id = enum {
-        Var,
-        Fn,
-        CompTime,
-    };
-
-    pub const Var = struct {
-        base: Decl,
-    };
-
-    pub const Fn = struct {
-        base: Decl,
-        value: union(enum) {
-            Unresolved,
-            Fn: *Value.Fn,
-            FnProto: *Value.FnProto,
-        },
-        fn_proto: *ast.Node.FnProto,
-
-        pub fn externLibName(self: Fn, tree: *ast.Tree) ?[]const u8 {
-            return if (self.fn_proto.extern_export_inline_token) |tok_index| x: {
-                const token = tree.tokens.at(tok_index);
-                break :x switch (token.id) {
-                    .Extern => tree.tokenSlicePtr(token),
-                    else => null,
-                };
-            } else null;
-        }
-
-        pub fn isExported(self: Fn, tree: *ast.Tree) bool {
-            if (self.fn_proto.extern_export_inline_token) |tok_index| {
-                const token = tree.tokens.at(tok_index);
-                return token.id == .Keyword_export;
-            } else {
-                return false;
-            }
-        }
-    };
-
-    pub const CompTime = struct {
-        base: Decl,
-    };
-};

src-self-hosted/errmsg.zig

@@ -1,284 +0,0 @@
-const std = @import("std");
-const mem = std.mem;
-const fs = std.fs;
-const process = std.process;
-const Token = std.zig.Token;
-const ast = std.zig.ast;
-const TokenIndex = std.zig.ast.TokenIndex;
-const Compilation = @import("compilation.zig").Compilation;
-const Scope = @import("scope.zig").Scope;
-
-pub const Color = enum {
-    Auto,
-    Off,
-    On,
-};
-
-pub const Span = struct {
-    first: ast.TokenIndex,
-    last: ast.TokenIndex,
-
-    pub fn token(i: TokenIndex) Span {
-        return Span{
-            .first = i,
-            .last = i,
-        };
-    }
-
-    pub fn node(n: *ast.Node) Span {
-        return Span{
-            .first = n.firstToken(),
-            .last = n.lastToken(),
-        };
-    }
-};
-
-pub const Msg = struct {
-    text: []u8,
-    realpath: []u8,
-    data: Data,
-
-    const Data = union(enum) {
-        Cli: Cli,
-        PathAndTree: PathAndTree,
-        ScopeAndComp: ScopeAndComp,
-    };
-
-    const PathAndTree = struct {
-        span: Span,
-        tree: *ast.Tree,
-        allocator: *mem.Allocator,
-    };
-
-    const ScopeAndComp = struct {
-        span: Span,
-        tree_scope: *Scope.AstTree,
-        compilation: *Compilation,
-    };
-
-    const Cli = struct {
-        allocator: *mem.Allocator,
-    };
-
-    pub fn destroy(self: *Msg) void {
-        switch (self.data) {
-            .Cli => |cli| {
-                cli.allocator.free(self.text);
-                cli.allocator.free(self.realpath);
-                cli.allocator.destroy(self);
-            },
-            .PathAndTree => |path_and_tree| {
-                path_and_tree.allocator.free(self.text);
-                path_and_tree.allocator.free(self.realpath);
-                path_and_tree.allocator.destroy(self);
-            },
-            .ScopeAndComp => |scope_and_comp| {
-                scope_and_comp.tree_scope.base.deref(scope_and_comp.compilation);
-                scope_and_comp.compilation.gpa().free(self.text);
-                scope_and_comp.compilation.gpa().free(self.realpath);
-                scope_and_comp.compilation.gpa().destroy(self);
-            },
-        }
-    }
-
-    fn getAllocator(self: *const Msg) *mem.Allocator {
-        switch (self.data) {
-            .Cli => |cli| return cli.allocator,
-            .PathAndTree => |path_and_tree| {
-                return path_and_tree.allocator;
-            },
-            .ScopeAndComp => |scope_and_comp| {
-                return scope_and_comp.compilation.gpa();
-            },
-        }
-    }
-
-    pub fn getTree(self: *const Msg) *ast.Tree {
-        switch (self.data) {
-            .Cli => unreachable,
-            .PathAndTree => |path_and_tree| {
-                return path_and_tree.tree;
-            },
-            .ScopeAndComp => |scope_and_comp| {
-                return scope_and_comp.tree_scope.tree;
-            },
-        }
-    }
-
-    pub fn getSpan(self: *const Msg) Span {
-        return switch (self.data) {
-            .Cli => unreachable,
-            .PathAndTree => |path_and_tree| path_and_tree.span,
-            .ScopeAndComp => |scope_and_comp| scope_and_comp.span,
-        };
-    }
-
-    /// Takes ownership of text
-    /// References tree_scope, and derefs when the msg is freed
-    pub fn createFromScope(comp: *Compilation, tree_scope: *Scope.AstTree, span: Span, text: []u8) !*Msg {
-        const realpath = try mem.dupe(comp.gpa(), u8, tree_scope.root().realpath);
-        errdefer comp.gpa().free(realpath);
-
-        const msg = try comp.gpa().create(Msg);
-        msg.* = Msg{
-            .text = text,
-            .realpath = realpath,
-            .data = Data{
-                .ScopeAndComp = ScopeAndComp{
-                    .tree_scope = tree_scope,
-                    .compilation = comp,
-                    .span = span,
-                },
-            },
-        };
-        tree_scope.base.ref();
-        return msg;
-    }
-
-    /// Caller owns returned Msg and must free with `allocator`
-    /// allocator will additionally be used for printing messages later.
-    pub fn createFromCli(comp: *Compilation, realpath: []const u8, text: []u8) !*Msg {
-        const realpath_copy = try mem.dupe(comp.gpa(), u8, realpath);
-        errdefer comp.gpa().free(realpath_copy);
-
-        const msg = try comp.gpa().create(Msg);
-        msg.* = Msg{
-            .text = text,
-            .realpath = realpath_copy,
-            .data = Data{
-                .Cli = Cli{ .allocator = comp.gpa() },
-            },
-        };
-        return msg;
-    }
-
-    pub fn createFromParseErrorAndScope(
-        comp: *Compilation,
-        tree_scope: *Scope.AstTree,
-        parse_error: *const ast.Error,
-    ) !*Msg {
-        const loc_token = parse_error.loc();
-        var text_buf = std.ArrayList(u8).init(comp.gpa());
-        defer text_buf.deinit();
-
-        const realpath_copy = try mem.dupe(comp.gpa(), u8, tree_scope.root().realpath);
-        errdefer comp.gpa().free(realpath_copy);
-
-        try parse_error.render(&tree_scope.tree.tokens, text_buf.outStream());
-
-        const msg = try comp.gpa().create(Msg);
-        msg.* = Msg{
-            .text = undefined,
-            .realpath = realpath_copy,
-            .data = Data{
-                .ScopeAndComp = ScopeAndComp{
-                    .tree_scope = tree_scope,
-                    .compilation = comp,
-                    .span = Span{
-                        .first = loc_token,
-                        .last = loc_token,
-                    },
-                },
-            },
-        };
-        tree_scope.base.ref();
-        msg.text = text_buf.toOwnedSlice();
-        return msg;
-    }
-
-    /// `realpath` must outlive the returned Msg
-    /// `tree` must outlive the returned Msg
-    /// Caller owns returned Msg and must free with `allocator`
-    /// allocator will additionally be used for printing messages later.
-    pub fn createFromParseError(
-        allocator: *mem.Allocator,
-        parse_error: *const ast.Error,
-        tree: *ast.Tree,
-        realpath: []const u8,
-    ) !*Msg {
-        const loc_token = parse_error.loc();
-        var text_buf = std.ArrayList(u8).init(allocator);
-        defer text_buf.deinit();
-
-        const realpath_copy = try mem.dupe(allocator, u8, realpath);
-        errdefer allocator.free(realpath_copy);
-
-        try parse_error.render(&tree.tokens, text_buf.outStream());
-
-        const msg = try allocator.create(Msg);
-        msg.* = Msg{
-            .text = undefined,
-            .realpath = realpath_copy,
-            .data = Data{
-                .PathAndTree = PathAndTree{
-                    .allocator = allocator,
-                    .tree = tree,
-                    .span = Span{
-                        .first = loc_token,
-                        .last = loc_token,
-                    },
-                },
-            },
-        };
-        msg.text = text_buf.toOwnedSlice();
-        errdefer allocator.destroy(msg);
-
-        return msg;
-    }
-
-    pub fn printToStream(msg: *const Msg, stream: var, color_on: bool) !void {
-        switch (msg.data) {
-            .Cli => {
-                try stream.print("{}:-:-: error: {}\n", .{ msg.realpath, msg.text });
-                return;
-            },
-            else => {},
-        }
-
-        const allocator = msg.getAllocator();
-        const tree = msg.getTree();
-
-        const cwd = try process.getCwdAlloc(allocator);
-        defer allocator.free(cwd);
-
-        const relpath = try fs.path.relative(allocator, cwd, msg.realpath);
-        defer allocator.free(relpath);
-
-        const path = if (relpath.len < msg.realpath.len) relpath else msg.realpath;
-        const span = msg.getSpan();
-
-        const first_token = tree.tokens.at(span.first);
-        const last_token = tree.tokens.at(span.last);
-        const start_loc = tree.tokenLocationPtr(0, first_token);
-        const end_loc = tree.tokenLocationPtr(first_token.end, last_token);
-        if (!color_on) {
-            try stream.print("{}:{}:{}: error: {}\n", .{
-                path,
-                start_loc.line + 1,
-                start_loc.column + 1,
-                msg.text,
-            });
-            return;
-        }
-
-        try stream.print("{}:{}:{}: error: {}\n{}\n", .{
-            path,
-            start_loc.line + 1,
-            start_loc.column + 1,
-            msg.text,
-            tree.source[start_loc.line_start..start_loc.line_end],
-        });
-        try stream.writeByteNTimes(' ', start_loc.column);
-        try stream.writeByteNTimes('~', last_token.end - first_token.start);
-        try stream.writeAll("\n");
-    }
-
-    pub fn printToFile(msg: *const Msg, file: fs.File, color: Color) !void {
-        const color_on = switch (color) {
-            .Auto => file.isTty(),
-            .On => true,
-            .Off => false,
-        };
-        return msg.printToStream(file.outStream(), color_on);
-    }
-};

src-self-hosted/libc_installation.zig

@@ -1,6 +1,5 @@
 const std = @import("std");
 const builtin = @import("builtin");
-const util = @import("util.zig");
 const Target = std.Target;
 const fs = std.fs;
 const Allocator = std.mem.Allocator;

src-self-hosted/package.zig

@@ -1,31 +0,0 @@
-const std = @import("std");
-const mem = std.mem;
-const assert = std.debug.assert;
-const ArrayListSentineled = std.ArrayListSentineled;
-
-pub const Package = struct {
-    root_src_dir: ArrayListSentineled(u8, 0),
-    root_src_path: ArrayListSentineled(u8, 0),
-
-    /// relative to root_src_dir
-    table: Table,
-
-    pub const Table = std.StringHashMap(*Package);
-
-    /// makes internal copies of root_src_dir and root_src_path
-    /// allocator should be an arena allocator because Package never frees anything
-    pub fn create(allocator: *mem.Allocator, root_src_dir: []const u8, root_src_path: []const u8) !*Package {
-        const ptr = try allocator.create(Package);
-        ptr.* = Package{
-            .root_src_dir = try ArrayListSentineled(u8, 0).init(allocator, root_src_dir),
-            .root_src_path = try ArrayListSentineled(u8, 0).init(allocator, root_src_path),
-            .table = Table.init(allocator),
-        };
-        return ptr;
-    }
-
-    pub fn add(self: *Package, name: []const u8, package: *Package) !void {
-        const entry = try self.table.put(try mem.dupe(self.table.allocator, u8, name), package);
-        assert(entry == null);
-    }
-};

src-self-hosted/scope.zig

@@ -1,418 +0,0 @@
-const std = @import("std");
-const Allocator = mem.Allocator;
-const Decl = @import("decl.zig").Decl;
-const Compilation = @import("compilation.zig").Compilation;
-const mem = std.mem;
-const ast = std.zig.ast;
-const Value = @import("value.zig").Value;
-const Type = @import("type.zig").Type;
-const ir = @import("ir.zig");
-const Span = @import("errmsg.zig").Span;
-const assert = std.debug.assert;
-const event = std.event;
-const llvm = @import("llvm.zig");
-
-pub const Scope = struct {
-    id: Id,
-    parent: ?*Scope,
-    ref_count: std.atomic.Int(usize),
-
-    /// Thread-safe
-    pub fn ref(base: *Scope) void {
-        _ = base.ref_count.incr();
-    }
-
-    /// Thread-safe
-    pub fn deref(base: *Scope, comp: *Compilation) void {
-        if (base.ref_count.decr() == 1) {
-            if (base.parent) |parent| parent.deref(comp);
-            switch (base.id) {
-                .Root => @fieldParentPtr(Root, "base", base).destroy(comp),
-                .Decls => @fieldParentPtr(Decls, "base", base).destroy(comp),
-                .Block => @fieldParentPtr(Block, "base", base).destroy(comp),
-                .FnDef => @fieldParentPtr(FnDef, "base", base).destroy(comp),
-                .CompTime => @fieldParentPtr(CompTime, "base", base).destroy(comp),
-                .Defer => @fieldParentPtr(Defer, "base", base).destroy(comp),
-                .DeferExpr => @fieldParentPtr(DeferExpr, "base", base).destroy(comp),
-                .Var => @fieldParentPtr(Var, "base", base).destroy(comp),
-                .AstTree => @fieldParentPtr(AstTree, "base", base).destroy(comp),
-            }
-        }
-    }
-
-    pub fn findRoot(base: *Scope) *Root {
-        var scope = base;
-        while (scope.parent) |parent| {
-            scope = parent;
-        }
-        assert(scope.id == .Root);
-        return @fieldParentPtr(Root, "base", scope);
-    }
-
-    pub fn findFnDef(base: *Scope) ?*FnDef {
-        var scope = base;
-        while (true) {
-            switch (scope.id) {
-                .FnDef => return @fieldParentPtr(FnDef, "base", scope),
-                .Root, .Decls => return null,
-
-                .Block,
-                .Defer,
-                .DeferExpr,
-                .CompTime,
-                .Var,
-                => scope = scope.parent.?,
-
-                .AstTree => unreachable,
-            }
-        }
-    }
-
-    pub fn findDeferExpr(base: *Scope) ?*DeferExpr {
-        var scope = base;
-        while (true) {
-            switch (scope.id) {
-                .DeferExpr => return @fieldParentPtr(DeferExpr, "base", scope),
-
-                .FnDef,
-                .Decls,
-                => return null,
-
-                .Block,
-                .Defer,
-                .CompTime,
-                .Root,
-                .Var,
-                => scope = scope.parent orelse return null,
-
-                .AstTree => unreachable,
-            }
-        }
-    }
-
-    fn init(base: *Scope, id: Id, parent: *Scope) void {
-        base.* = Scope{
-            .id = id,
-            .parent = parent,
-            .ref_count = std.atomic.Int(usize).init(1),
-        };
-        parent.ref();
-    }
-
-    pub const Id = enum {
-        Root,
-        AstTree,
-        Decls,
-        Block,
-        FnDef,
-        CompTime,
-        Defer,
-        DeferExpr,
-        Var,
-    };
-
-    pub const Root = struct {
-        base: Scope,
-        realpath: []const u8,
-        decls: *Decls,
-
-        /// Creates a Root scope with 1 reference
-        /// Takes ownership of realpath
-        pub fn create(comp: *Compilation, realpath: []u8) !*Root {
-            const self = try comp.gpa().create(Root);
-            self.* = Root{
-                .base = Scope{
-                    .id = .Root,
-                    .parent = null,
-                    .ref_count = std.atomic.Int(usize).init(1),
-                },
-                .realpath = realpath,
-                .decls = undefined,
-            };
-            errdefer comp.gpa().destroy(self);
-            self.decls = try Decls.create(comp, &self.base);
-            return self;
-        }
-
-        pub fn destroy(self: *Root, comp: *Compilation) void {
-            // TODO comp.fs_watch.removeFile(self.realpath);
-            self.decls.base.deref(comp);
-            comp.gpa().free(self.realpath);
-            comp.gpa().destroy(self);
-        }
-    };
-
-    pub const AstTree = struct {
-        base: Scope,
-        tree: *ast.Tree,
-
-        /// Creates a scope with 1 reference
-        /// Takes ownership of tree, will deinit and destroy when done.
-        pub fn create(comp: *Compilation, tree: *ast.Tree, root_scope: *Root) !*AstTree {
-            const self = try comp.gpa().create(AstTree);
-            self.* = AstTree{
-                .base = undefined,
-                .tree = tree,
-            };
-            self.base.init(.AstTree, &root_scope.base);
-
-            return self;
-        }
-
-        pub fn destroy(self: *AstTree, comp: *Compilation) void {
-            comp.gpa().free(self.tree.source);
-            self.tree.deinit();
-            comp.gpa().destroy(self);
-        }
-
-        pub fn root(self: *AstTree) *Root {
-            return self.base.findRoot();
-        }
-    };
-
-    pub const Decls = struct {
-        base: Scope,
-
-        /// This table remains Write Locked when the names are incomplete or possibly outdated.
-        /// So if a reader manages to grab a lock, it can be sure that the set of names is complete
-        /// and correct.
-        table: event.RwLocked(Decl.Table),
-
-        /// Creates a Decls scope with 1 reference
-        pub fn create(comp: *Compilation, parent: *Scope) !*Decls {
-            const self = try comp.gpa().create(Decls);
-            self.* = Decls{
-                .base = undefined,
-                .table = event.RwLocked(Decl.Table).init(Decl.Table.init(comp.gpa())),
-            };
-            self.base.init(.Decls, parent);
-            return self;
-        }
-
-        pub fn destroy(self: *Decls, comp: *Compilation) void {
-            self.table.deinit();
-            comp.gpa().destroy(self);
-        }
-    };
-
-    pub const Block = struct {
-        base: Scope,
-        incoming_values: std.ArrayList(*ir.Inst),
-        incoming_blocks: std.ArrayList(*ir.BasicBlock),
-        end_block: *ir.BasicBlock,
-        is_comptime: *ir.Inst,
-
-        safety: Safety,
-
-        const Safety = union(enum) {
-            Auto,
-            Manual: Manual,
-
-            const Manual = struct {
-                /// the source span that disabled the safety value
-                span: Span,
-
-                /// whether safety is enabled
-                enabled: bool,
-            };
-
-            fn get(self: Safety, comp: *Compilation) bool {
-                return switch (self) {
-                    .Auto => switch (comp.build_mode) {
-                        .Debug,
-                        .ReleaseSafe,
-                        => true,
-                        .ReleaseFast,
-                        .ReleaseSmall,
-                        => false,
-                    },
-                    .Manual => |man| man.enabled,
-                };
-            }
-        };
-
-        /// Creates a Block scope with 1 reference
-        pub fn create(comp: *Compilation, parent: *Scope) !*Block {
-            const self = try comp.gpa().create(Block);
-            self.* = Block{
-                .base = undefined,
-                .incoming_values = undefined,
-                .incoming_blocks = undefined,
-                .end_block = undefined,
-                .is_comptime = undefined,
-                .safety = Safety.Auto,
-            };
-            self.base.init(.Block, parent);
-            return self;
-        }
-
-        pub fn destroy(self: *Block, comp: *Compilation) void {
-            comp.gpa().destroy(self);
-        }
-    };
-
-    pub const FnDef = struct {
-        base: Scope,
-
-        /// This reference is not counted so that the scope can get destroyed with the function
-        fn_val: ?*Value.Fn,
-
-        /// Creates a FnDef scope with 1 reference
-        /// Must set the fn_val later
-        pub fn create(comp: *Compilation, parent: *Scope) !*FnDef {
-            const self = try comp.gpa().create(FnDef);
-            self.* = FnDef{
-                .base = undefined,
-                .fn_val = null,
-            };
-            self.base.init(.FnDef, parent);
-            return self;
-        }
-
-        pub fn destroy(self: *FnDef, comp: *Compilation) void {
-            comp.gpa().destroy(self);
-        }
-    };
-
-    pub const CompTime = struct {
-        base: Scope,
-
-        /// Creates a CompTime scope with 1 reference
-        pub fn create(comp: *Compilation, parent: *Scope) !*CompTime {
-            const self = try comp.gpa().create(CompTime);
-            self.* = CompTime{ .base = undefined };
-            self.base.init(.CompTime, parent);
-            return self;
-        }
-
-        pub fn destroy(self: *CompTime, comp: *Compilation) void {
-            comp.gpa().destroy(self);
-        }
-    };
-
-    pub const Defer = struct {
-        base: Scope,
-        defer_expr_scope: *DeferExpr,
-        kind: Kind,
-
-        pub const Kind = enum {
-            ScopeExit,
-            ErrorExit,
-        };
-
-        /// Creates a Defer scope with 1 reference
-        pub fn create(
-            comp: *Compilation,
-            parent: *Scope,
-            kind: Kind,
-            defer_expr_scope: *DeferExpr,
-        ) !*Defer {
-            const self = try comp.gpa().create(Defer);
-            self.* = Defer{
-                .base = undefined,
-                .defer_expr_scope = defer_expr_scope,
-                .kind = kind,
-            };
-            self.base.init(.Defer, parent);
-            defer_expr_scope.base.ref();
-            return self;
-        }
-
-        pub fn destroy(self: *Defer, comp: *Compilation) void {
-            self.defer_expr_scope.base.deref(comp);
-            comp.gpa().destroy(self);
-        }
-    };
-
-    pub const DeferExpr = struct {
-        base: Scope,
-        expr_node: *ast.Node,
-        reported_err: bool,
-
-        /// Creates a DeferExpr scope with 1 reference
-        pub fn create(comp: *Compilation, parent: *Scope, expr_node: *ast.Node) !*DeferExpr {
-            const self = try comp.gpa().create(DeferExpr);
-            self.* = DeferExpr{
-                .base = undefined,
-                .expr_node = expr_node,
-                .reported_err = false,
-            };
-            self.base.init(.DeferExpr, parent);
-            return self;
-        }
-
-        pub fn destroy(self: *DeferExpr, comp: *Compilation) void {
-            comp.gpa().destroy(self);
-        }
-    };
-
-    pub const Var = struct {
-        base: Scope,
-        name: []const u8,
-        src_node: *ast.Node,
-        data: Data,
-
-        pub const Data = union(enum) {
-            Param: Param,
-            Const: *Value,
-        };
-
-        pub const Param = struct {
-            index: usize,
-            typ: *Type,
-            llvm_value: *llvm.Value,
-        };
-
-        pub fn createParam(
-            comp: *Compilation,
-            parent: *Scope,
-            name: []const u8,
-            src_node: *ast.Node,
-            param_index: usize,
-            param_type: *Type,
-        ) !*Var {
-            const self = try create(comp, parent, name, src_node);
-            self.data = Data{
-                .Param = Param{
-                    .index = param_index,
-                    .typ = param_type,
-                    .llvm_value = undefined,
-                },
-            };
-            return self;
-        }
-
-        pub fn createConst(
-            comp: *Compilation,
-            parent: *Scope,
-            name: []const u8,
-            src_node: *ast.Node,
-            value: *Value,
-        ) !*Var {
-            const self = try create(comp, parent, name, src_node);
-            self.data = Data{ .Const = value };
-            value.ref();
-            return self;
-        }
-
-        fn create(comp: *Compilation, parent: *Scope, name: []const u8, src_node: *ast.Node) !*Var {
-            const self = try comp.gpa().create(Var);
-            self.* = Var{
-                .base = undefined,
-                .name = name,
-                .src_node = src_node,
-                .data = undefined,
-            };
-            self.base.init(.Var, parent);
-            return self;
-        }
-
-        pub fn destroy(self: *Var, comp: *Compilation) void {
-            switch (self.data) {
-                .Param => {},
-                .Const => |value| value.deref(comp),
-            }
-            comp.gpa().destroy(self);
-        }
-    };
-};

src-self-hosted/stage2.zig

@@ -12,7 +12,6 @@ const ArrayListSentineled = std.ArrayListSentineled;
 const Target = std.Target;
 const CrossTarget = std.zig.CrossTarget;
 const self_hosted_main = @import("main.zig");
-const errmsg = @import("errmsg.zig");
 const DepTokenizer = @import("dep_tokenizer.zig").Tokenizer;
 const assert = std.debug.assert;
 const LibCInstallation = @import("libc_installation.zig").LibCInstallation;
@@ -168,8 +167,6 @@ export fn stage2_render_ast(tree: *ast.Tree, output_file: *FILE) Error {
     return .None;
 }
 
-// TODO: just use the actual self-hosted zig fmt. Until https://github.com/ziglang/zig/issues/2377,
-// we use a blocking implementation.
 export fn stage2_fmt(argc: c_int, argv: [*]const [*:0]const u8) c_int {
     if (std.debug.runtime_safety) {
         fmtMain(argc, argv) catch unreachable;
@@ -191,258 +188,9 @@ fn fmtMain(argc: c_int, argv: [*]const [*:0]const u8) !void {
         try args_list.append(mem.spanZ(argv[arg_i]));
     }
 
-    stdout = std.io.getStdOut().outStream();
-    stderr_file = std.io.getStdErr();
-    stderr = stderr_file.outStream();
-
     const args = args_list.span()[2..];
 
-    var color: errmsg.Color = .Auto;
-    var stdin_flag: bool = false;
-    var check_flag: bool = false;
-    var input_files = ArrayList([]const u8).init(allocator);
-
-    {
-        var i: usize = 0;
-        while (i < args.len) : (i += 1) {
-            const arg = args[i];
-            if (mem.startsWith(u8, arg, "-")) {
-                if (mem.eql(u8, arg, "--help")) {
-                    try stdout.writeAll(self_hosted_main.usage_fmt);
-                    process.exit(0);
-                } else if (mem.eql(u8, arg, "--color")) {
-                    if (i + 1 >= args.len) {
-                        try stderr.writeAll("expected [auto|on|off] after --color\n");
-                        process.exit(1);
-                    }
-                    i += 1;
-                    const next_arg = args[i];
-                    if (mem.eql(u8, next_arg, "auto")) {
-                        color = .Auto;
-                    } else if (mem.eql(u8, next_arg, "on")) {
-                        color = .On;
-                    } else if (mem.eql(u8, next_arg, "off")) {
-                        color = .Off;
-                    } else {
-                        try stderr.print("expected [auto|on|off] after --color, found '{}'\n", .{next_arg});
-                        process.exit(1);
-                    }
-                } else if (mem.eql(u8, arg, "--stdin")) {
-                    stdin_flag = true;
-                } else if (mem.eql(u8, arg, "--check")) {
-                    check_flag = true;
-                } else {
-                    try stderr.print("unrecognized parameter: '{}'", .{arg});
-                    process.exit(1);
-                }
-            } else {
-                try input_files.append(arg);
-            }
-        }
-    }
-
-    if (stdin_flag) {
-        if (input_files.items.len != 0) {
-            try stderr.writeAll("cannot use --stdin with positional arguments\n");
-            process.exit(1);
-        }
-
-        const stdin_file = io.getStdIn();
-        var stdin = stdin_file.inStream();
-
-        const source_code = try stdin.readAllAlloc(allocator, self_hosted_main.max_src_size);
-        defer allocator.free(source_code);
-
-        const tree = std.zig.parse(allocator, source_code) catch |err| {
-            try stderr.print("error parsing stdin: {}\n", .{err});
-            process.exit(1);
-        };
-        defer tree.deinit();
-
-        var error_it = tree.errors.iterator(0);
-        while (error_it.next()) |parse_error| {
-            try printErrMsgToFile(allocator, parse_error, tree, "<stdin>", stderr_file, color);
-        }
-        if (tree.errors.len != 0) {
-            process.exit(1);
-        }
-        if (check_flag) {
-            const anything_changed = try std.zig.render(allocator, io.null_out_stream, tree);
-            const code = if (anything_changed) @as(u8, 1) else @as(u8, 0);
-            process.exit(code);
-        }
-
-        _ = try std.zig.render(allocator, stdout, tree);
-        return;
-    }
-
-    if (input_files.items.len == 0) {
-        try stderr.writeAll("expected at least one source file argument\n");
-        process.exit(1);
-    }
-
-    var fmt = Fmt{
-        .seen = Fmt.SeenMap.init(allocator),
-        .any_error = false,
-        .color = color,
-        .allocator = allocator,
-    };
-
-    for (input_files.span()) |file_path| {
-        try fmtPath(&fmt, file_path, check_flag);
-    }
-    if (fmt.any_error) {
-        process.exit(1);
-    }
-}
-
-const FmtError = error{
-    SystemResources,
-    OperationAborted,
-    IoPending,
-    BrokenPipe,
-    Unexpected,
-    WouldBlock,
-    FileClosed,
-    DestinationAddressRequired,
-    DiskQuota,
-    FileTooBig,
-    InputOutput,
-    NoSpaceLeft,
-    AccessDenied,
-    OutOfMemory,
-    RenameAcrossMountPoints,
-    ReadOnlyFileSystem,
-    LinkQuotaExceeded,
-    FileBusy,
-} || fs.File.OpenError;
-
-fn fmtPath(fmt: *Fmt, file_path: []const u8, check_mode: bool) FmtError!void {
-    // get the real path here to avoid Windows failing on relative file paths with . or .. in them
-    var real_path = fs.realpathAlloc(fmt.allocator, file_path) catch |err| {
-        try stderr.print("unable to open '{}': {}\n", .{ file_path, err });
-        fmt.any_error = true;
-        return;
-    };
-    defer fmt.allocator.free(real_path);
-
-    if (fmt.seen.exists(real_path)) return;
-    try fmt.seen.put(real_path);
-
-    const source_code = fs.cwd().readFileAlloc(fmt.allocator, real_path, self_hosted_main.max_src_size) catch |err| switch (err) {
-        error.IsDir, error.AccessDenied => {
-            // TODO make event based (and dir.next())
-            var dir = try fs.cwd().openDir(file_path, .{ .iterate = true });
-            defer dir.close();
-
-            var dir_it = dir.iterate();
-
-            while (try dir_it.next()) |entry| {
-                if (entry.kind == .Directory or mem.endsWith(u8, entry.name, ".zig")) {
-                    const full_path = try fs.path.join(fmt.allocator, &[_][]const u8{ file_path, entry.name });
-                    try fmtPath(fmt, full_path, check_mode);
-                }
-            }
-            return;
-        },
-        else => {
-            // TODO lock stderr printing
-            try stderr.print("unable to open '{}': {}\n", .{ file_path, err });
-            fmt.any_error = true;
-            return;
-        },
-    };
-    defer fmt.allocator.free(source_code);
-
-    const tree = std.zig.parse(fmt.allocator, source_code) catch |err| {
-        try stderr.print("error parsing file '{}': {}\n", .{ file_path, err });
-        fmt.any_error = true;
-        return;
-    };
-    defer tree.deinit();
-
-    var error_it = tree.errors.iterator(0);
-    while (error_it.next()) |parse_error| {
-        try printErrMsgToFile(fmt.allocator, parse_error, tree, file_path, stderr_file, fmt.color);
-    }
-    if (tree.errors.len != 0) {
-        fmt.any_error = true;
-        return;
-    }
-
-    if (check_mode) {
-        const anything_changed = try std.zig.render(fmt.allocator, io.null_out_stream, tree);
-        if (anything_changed) {
-            try stderr.print("{}\n", .{file_path});
-            fmt.any_error = true;
-        }
-    } else {
-        const baf = try io.BufferedAtomicFile.create(fmt.allocator, fs.cwd(), real_path, .{});
-        defer baf.destroy();
-
-        const anything_changed = try std.zig.render(fmt.allocator, baf.stream(), tree);
-        if (anything_changed) {
-            try stderr.print("{}\n", .{file_path});
-            try baf.finish();
-        }
-    }
-}
-
-const Fmt = struct {
-    seen: SeenMap,
-    any_error: bool,
-    color: errmsg.Color,
-    allocator: *mem.Allocator,
-
-    const SeenMap = std.BufSet;
-};
-
-fn printErrMsgToFile(
-    allocator: *mem.Allocator,
-    parse_error: *const ast.Error,
-    tree: *ast.Tree,
-    path: []const u8,
-    file: fs.File,
-    color: errmsg.Color,
-) !void {
-    const color_on = switch (color) {
-        .Auto => file.isTty(),
-        .On => true,
-        .Off => false,
-    };
-    const lok_token = parse_error.loc();
-    const span = errmsg.Span{
-        .first = lok_token,
-        .last = lok_token,
-    };
-
-    const first_token = tree.tokens.at(span.first);
-    const last_token = tree.tokens.at(span.last);
-    const start_loc = tree.tokenLocationPtr(0, first_token);
-    const end_loc = tree.tokenLocationPtr(first_token.end, last_token);
-
-    var text_buf = std.ArrayList(u8).init(allocator);
-    defer text_buf.deinit();
-    const out_stream = text_buf.outStream();
-    try parse_error.render(&tree.tokens, out_stream);
-    const text = text_buf.span();
-
-    const stream = file.outStream();
-    try stream.print("{}:{}:{}: error: {}\n", .{ path, start_loc.line + 1, start_loc.column + 1, text });
-
-    if (!color_on) return;
-
-    // Print \r and \t as one space each so that column counts line up
-    for (tree.source[start_loc.line_start..start_loc.line_end]) |byte| {
-        try stream.writeByte(switch (byte) {
-            '\r', '\t' => ' ',
-            else => byte,
-        });
-    }
-    try stream.writeByte('\n');
-    try stream.writeByteNTimes(' ', start_loc.column);
-    try stream.writeByteNTimes('~', last_token.end - first_token.start);
-    try stream.writeByte('\n');
+    return self_hosted_main.cmdFmt(allocator, args);
 }
 
 export fn stage2_DepTokenizer_init(input: [*]const u8, len: usize) stage2_DepTokenizer {

src-self-hosted/test.zig

@@ -1,17 +1,18 @@
 const std = @import("std");
 const link = @import("link.zig");
-const ir = @import("ir.zig");
+const Module = @import("Module.zig");
 const Allocator = std.mem.Allocator;
-
-var global_ctx: TestContext = undefined;
+const zir = @import("zir.zig");
+const Package = @import("Package.zig");
 
 test "self-hosted" {
-    try global_ctx.init();
-    defer global_ctx.deinit();
+    var ctx: TestContext = undefined;
+    try ctx.init();
+    defer ctx.deinit();
 
-    try @import("stage2_tests").addCases(&global_ctx);
+    try @import("stage2_tests").addCases(&ctx);
 
-    try global_ctx.run();
+    try ctx.run();
 }
 
 pub const TestContext = struct {
@@ -20,32 +21,34 @@ pub const TestContext = struct {
 
     pub const ZIRCompareOutputCase = struct {
         name: []const u8,
-        src: [:0]const u8,
-        expected_stdout: []const u8,
+        src_list: []const []const u8,
+        expected_stdout_list: []const []const u8,
     };
 
     pub const ZIRTransformCase = struct {
         name: []const u8,
         src: [:0]const u8,
         expected_zir: []const u8,
+        cross_target: std.zig.CrossTarget,
     };
 
     pub fn addZIRCompareOutput(
         ctx: *TestContext,
         name: []const u8,
-        src: [:0]const u8,
-        expected_stdout: []const u8,
+        src_list: []const []const u8,
+        expected_stdout_list: []const []const u8,
     ) void {
         ctx.zir_cmp_output_cases.append(.{
             .name = name,
-            .src = src,
-            .expected_stdout = expected_stdout,
+            .src_list = src_list,
+            .expected_stdout_list = expected_stdout_list,
         }) catch unreachable;
     }
 
     pub fn addZIRTransform(
         ctx: *TestContext,
         name: []const u8,
+        cross_target: std.zig.CrossTarget,
         src: [:0]const u8,
         expected_zir: []const u8,
     ) void {
@@ -53,6 +56,7 @@ pub const TestContext = struct {
             .name = name,
             .src = src,
             .expected_zir = expected_zir,
+            .cross_target = cross_target,
         }) catch unreachable;
     }
 
@@ -84,7 +88,8 @@ pub const TestContext = struct {
         }
         for (self.zir_transform_cases.items) |case| {
             std.testing.base_allocator_instance.reset();
-            try self.runOneZIRTransformCase(std.testing.allocator, root_node, case, native_info.target);
+            const info = try std.zig.system.NativeTargetInfo.detect(std.testing.allocator, case.cross_target);
+            try self.runOneZIRTransformCase(std.testing.allocator, root_node, case, info.target);
             try std.testing.allocator_instance.validate();
         }
     }
@@ -99,77 +104,68 @@ pub const TestContext = struct {
         var tmp = std.testing.tmpDir(.{});
         defer tmp.cleanup();
 
-        var prg_node = root_node.start(case.name, 4);
+        const tmp_src_path = "test-case.zir";
+        const root_pkg = try Package.create(allocator, tmp.dir, ".", tmp_src_path);
+        defer root_pkg.destroy();
+
+        var prg_node = root_node.start(case.name, case.src_list.len);
         prg_node.activate();
         defer prg_node.end();
 
-        var zir_module = x: {
-            var parse_node = prg_node.start("parse", null);
-            parse_node.activate();
-            defer parse_node.end();
+        var module = try Module.init(allocator, .{
+            .target = target,
+            .output_mode = .Exe,
+            .optimize_mode = .Debug,
+            .bin_file_dir = tmp.dir,
+            .bin_file_path = "a.out",
+            .root_pkg = root_pkg,
+        });
+        defer module.deinit();
 
-            break :x try ir.text.parse(allocator, case.src);
-        };
-        defer zir_module.deinit(allocator);
-        if (zir_module.errors.len != 0) {
-            debugPrintErrors(case.src, zir_module.errors);
-            return error.ParseFailure;
+        for (case.src_list) |source, i| {
+            var src_node = prg_node.start("update", 2);
+            src_node.activate();
+            defer src_node.end();
+
+            try tmp.dir.writeFile(tmp_src_path, source);
+
+            var update_node = src_node.start("parse,analysis,codegen", null);
+            update_node.activate();
+            try module.makeBinFileWritable();
+            try module.update();
+            update_node.end();
+
+            var exec_result = x: {
+                var exec_node = src_node.start("execute", null);
+                exec_node.activate();
+                defer exec_node.end();
+
+                try module.makeBinFileExecutable();
+                break :x try std.ChildProcess.exec(.{
+                    .allocator = allocator,
+                    .argv = &[_][]const u8{"./a.out"},
+                    .cwd_dir = tmp.dir,
+                });
+            };
+            defer allocator.free(exec_result.stdout);
+            defer allocator.free(exec_result.stderr);
+            switch (exec_result.term) {
+                .Exited => |code| {
+                    if (code != 0) {
+                        std.debug.warn("elf file exited with code {}\n", .{code});
+                        return error.BinaryBadExitCode;
+                    }
+                },
+                else => return error.BinaryCrashed,
+            }
+            const expected_stdout = case.expected_stdout_list[i];
+            if (!std.mem.eql(u8, expected_stdout, exec_result.stdout)) {
+                std.debug.panic(
+                    "update index {}, mismatched stdout\n====Expected (len={}):====\n{}\n====Actual (len={}):====\n{}\n========\n",
+                    .{ i, expected_stdout.len, expected_stdout, exec_result.stdout.len, exec_result.stdout },
+                );
+            }
         }
-
-        var analyzed_module = x: {
-            var analyze_node = prg_node.start("analyze", null);
-            analyze_node.activate();
-            defer analyze_node.end();
-
-            break :x try ir.analyze(allocator, zir_module, .{
-                .target = target,
-                .output_mode = .Exe,
-                .link_mode = .Static,
-                .optimize_mode = .Debug,
-            });
-        };
-        defer analyzed_module.deinit(allocator);
-        if (analyzed_module.errors.len != 0) {
-            debugPrintErrors(case.src, analyzed_module.errors);
-            return error.ParseFailure;
-        }
-
-        var link_result = x: {
-            var link_node = prg_node.start("link", null);
-            link_node.activate();
-            defer link_node.end();
-
-            break :x try link.updateFilePath(allocator, analyzed_module, tmp.dir, "a.out");
-        };
-        defer link_result.deinit(allocator);
-        if (link_result.errors.len != 0) {
-            debugPrintErrors(case.src, link_result.errors);
-            return error.LinkFailure;
-        }
-
-        var exec_result = x: {
-            var exec_node = prg_node.start("execute", null);
-            exec_node.activate();
-            defer exec_node.end();
-
-            break :x try std.ChildProcess.exec(.{
-                .allocator = allocator,
-                .argv = &[_][]const u8{"./a.out"},
-                .cwd_dir = tmp.dir,
-            });
-        };
-        defer allocator.free(exec_result.stdout);
-        defer allocator.free(exec_result.stderr);
-        switch (exec_result.term) {
-            .Exited => |code| {
-                if (code != 0) {
-                    std.debug.warn("elf file exited with code {}\n", .{code});
-                    return error.BinaryBadExitCode;
-                }
-            },
-            else => return error.BinaryCrashed,
-        }
-        std.testing.expectEqualSlices(u8, case.expected_stdout, exec_result.stdout);
     }
 
     fn runOneZIRTransformCase(
@@ -179,38 +175,37 @@ pub const TestContext = struct {
         case: ZIRTransformCase,
         target: std.Target,
     ) !void {
-        var prg_node = root_node.start(case.name, 4);
+        var tmp = std.testing.tmpDir(.{});
+        defer tmp.cleanup();
+
+        var prg_node = root_node.start(case.name, 3);
         prg_node.activate();
         defer prg_node.end();
 
-        var parse_node = prg_node.start("parse", null);
-        parse_node.activate();
-        var zir_module = try ir.text.parse(allocator, case.src);
-        defer zir_module.deinit(allocator);
-        if (zir_module.errors.len != 0) {
-            debugPrintErrors(case.src, zir_module.errors);
-            return error.ParseFailure;
-        }
-        parse_node.end();
+        const tmp_src_path = "test-case.zir";
+        try tmp.dir.writeFile(tmp_src_path, case.src);
 
-        var analyze_node = prg_node.start("analyze", null);
-        analyze_node.activate();
-        var analyzed_module = try ir.analyze(allocator, zir_module, .{
+        const root_pkg = try Package.create(allocator, tmp.dir, ".", tmp_src_path);
+        defer root_pkg.destroy();
+
+        var module = try Module.init(allocator, .{
             .target = target,
             .output_mode = .Obj,
-            .link_mode = .Static,
             .optimize_mode = .Debug,
+            .bin_file_dir = tmp.dir,
+            .bin_file_path = "test-case.o",
+            .root_pkg = root_pkg,
         });
-        defer analyzed_module.deinit(allocator);
-        if (analyzed_module.errors.len != 0) {
-            debugPrintErrors(case.src, analyzed_module.errors);
-            return error.ParseFailure;
-        }
-        analyze_node.end();
+        defer module.deinit();
+
+        var module_node = prg_node.start("parse/analysis/codegen", null);
+        module_node.activate();
+        try module.update();
+        module_node.end();
 
         var emit_node = prg_node.start("emit", null);
         emit_node.activate();
-        var new_zir_module = try ir.text.emit_zir(allocator, analyzed_module);
+        var new_zir_module = try zir.emit(allocator, module);
         defer new_zir_module.deinit(allocator);
         emit_node.end();
 

src-self-hosted/type.zig

@@ -5,8 +5,7 @@ const Allocator = std.mem.Allocator;
 const Target = std.Target;
 
 /// This is the raw data, with no bookkeeping, no memory awareness, no de-duplication.
-/// It's important for this struct to be small.
-/// It is not copyable since it may contain references to its inner data.
+/// It's important for this type to be small.
 /// Types are not de-duplicated, which helps with multi-threading since it obviates the requirement
 /// of obtaining a lock on a global type table, as well as making the
 /// garbage collection bookkeeping simpler.
@@ -51,7 +50,9 @@ pub const Type = extern union {
             .comptime_int => return .ComptimeInt,
             .comptime_float => return .ComptimeFloat,
             .noreturn => return .NoReturn,
+            .@"null" => return .Null,
 
+            .fn_noreturn_no_args => return .Fn,
             .fn_naked_noreturn_no_args => return .Fn,
             .fn_ccc_void_no_args => return .Fn,
 
@@ -183,7 +184,10 @@ pub const Type = extern union {
                 .noreturn,
                 => return out_stream.writeAll(@tagName(t)),
 
+                .@"null" => return out_stream.writeAll("@TypeOf(null)"),
+
                 .const_slice_u8 => return out_stream.writeAll("[]const u8"),
+                .fn_noreturn_no_args => return out_stream.writeAll("fn() noreturn"),
                 .fn_naked_noreturn_no_args => return out_stream.writeAll("fn() callconv(.Naked) noreturn"),
                 .fn_ccc_void_no_args => return out_stream.writeAll("fn() callconv(.C) void"),
                 .single_const_pointer_to_comptime_int => return out_stream.writeAll("*const comptime_int"),
@@ -244,6 +248,8 @@ pub const Type = extern union {
             .comptime_int => return Value.initTag(.comptime_int_type),
             .comptime_float => return Value.initTag(.comptime_float_type),
             .noreturn => return Value.initTag(.noreturn_type),
+            .@"null" => return Value.initTag(.null_type),
+            .fn_noreturn_no_args => return Value.initTag(.fn_noreturn_no_args_type),
             .fn_naked_noreturn_no_args => return Value.initTag(.fn_naked_noreturn_no_args_type),
             .fn_ccc_void_no_args => return Value.initTag(.fn_ccc_void_no_args_type),
             .single_const_pointer_to_comptime_int => return Value.initTag(.single_const_pointer_to_comptime_int_type),
@@ -256,6 +262,110 @@ pub const Type = extern union {
         }
     }
 
+    pub fn hasCodeGenBits(self: Type) bool {
+        return switch (self.tag()) {
+            .u8,
+            .i8,
+            .isize,
+            .usize,
+            .c_short,
+            .c_ushort,
+            .c_int,
+            .c_uint,
+            .c_long,
+            .c_ulong,
+            .c_longlong,
+            .c_ulonglong,
+            .c_longdouble,
+            .f16,
+            .f32,
+            .f64,
+            .f128,
+            .bool,
+            .anyerror,
+            .fn_noreturn_no_args,
+            .fn_naked_noreturn_no_args,
+            .fn_ccc_void_no_args,
+            .single_const_pointer_to_comptime_int,
+            .const_slice_u8,
+            .array_u8_sentinel_0,
+            .array, // TODO check for zero bits
+            .single_const_pointer,
+            .int_signed, // TODO check for zero bits
+            .int_unsigned, // TODO check for zero bits
+            => true,
+
+            .c_void,
+            .void,
+            .type,
+            .comptime_int,
+            .comptime_float,
+            .noreturn,
+            .@"null",
+            => false,
+        };
+    }
+
+    /// Asserts that hasCodeGenBits() is true.
+    pub fn abiAlignment(self: Type, target: Target) u32 {
+        return switch (self.tag()) {
+            .u8,
+            .i8,
+            .bool,
+            .fn_noreturn_no_args, // represents machine code; not a pointer
+            .fn_naked_noreturn_no_args, // represents machine code; not a pointer
+            .fn_ccc_void_no_args, // represents machine code; not a pointer
+            .array_u8_sentinel_0,
+            => return 1,
+
+            .isize,
+            .usize,
+            .single_const_pointer_to_comptime_int,
+            .const_slice_u8,
+            .single_const_pointer,
+            => return @divExact(target.cpu.arch.ptrBitWidth(), 8),
+
+            .c_short => return @divExact(CType.short.sizeInBits(target), 8),
+            .c_ushort => return @divExact(CType.ushort.sizeInBits(target), 8),
+            .c_int => return @divExact(CType.int.sizeInBits(target), 8),
+            .c_uint => return @divExact(CType.uint.sizeInBits(target), 8),
+            .c_long => return @divExact(CType.long.sizeInBits(target), 8),
+            .c_ulong => return @divExact(CType.ulong.sizeInBits(target), 8),
+            .c_longlong => return @divExact(CType.longlong.sizeInBits(target), 8),
+            .c_ulonglong => return @divExact(CType.ulonglong.sizeInBits(target), 8),
+
+            .f16 => return 2,
+            .f32 => return 4,
+            .f64 => return 8,
+            .f128 => return 16,
+            .c_longdouble => return 16,
+
+            .anyerror => return 2, // TODO revisit this when we have the concept of the error tag type
+
+            .array => return self.cast(Payload.Array).?.elem_type.abiAlignment(target),
+
+            .int_signed, .int_unsigned => {
+                const bits: u16 = if (self.cast(Payload.IntSigned)) |pl|
+                    pl.bits
+                else if (self.cast(Payload.IntUnsigned)) |pl|
+                    pl.bits
+                else
+                    unreachable;
+
+                return std.math.ceilPowerOfTwoPromote(u16, (bits + 7) / 8);
+            },
+
+            .c_void,
+            .void,
+            .type,
+            .comptime_int,
+            .comptime_float,
+            .noreturn,
+            .@"null",
+            => unreachable,
+        };
+    }
+
     pub fn isSinglePointer(self: Type) bool {
         return switch (self.tag()) {
             .u8,
@@ -283,9 +393,11 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
             .array,
             .array_u8_sentinel_0,
             .const_slice_u8,
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .int_unsigned,
@@ -325,10 +437,12 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
             .array,
             .array_u8_sentinel_0,
             .single_const_pointer,
             .single_const_pointer_to_comptime_int,
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .int_unsigned,
@@ -367,8 +481,10 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
             .array,
             .array_u8_sentinel_0,
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .int_unsigned,
@@ -410,6 +526,8 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .int_unsigned,
@@ -451,6 +569,8 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .single_const_pointer,
@@ -465,6 +585,50 @@ pub const Type = extern union {
         };
     }
 
+    /// Asserts the type is an array or vector.
+    pub fn arraySentinel(self: Type) ?Value {
+        return switch (self.tag()) {
+            .u8,
+            .i8,
+            .isize,
+            .usize,
+            .c_short,
+            .c_ushort,
+            .c_int,
+            .c_uint,
+            .c_long,
+            .c_ulong,
+            .c_longlong,
+            .c_ulonglong,
+            .c_longdouble,
+            .f16,
+            .f32,
+            .f64,
+            .f128,
+            .c_void,
+            .bool,
+            .void,
+            .type,
+            .anyerror,
+            .comptime_int,
+            .comptime_float,
+            .noreturn,
+            .@"null",
+            .fn_noreturn_no_args,
+            .fn_naked_noreturn_no_args,
+            .fn_ccc_void_no_args,
+            .single_const_pointer,
+            .single_const_pointer_to_comptime_int,
+            .const_slice_u8,
+            .int_unsigned,
+            .int_signed,
+            => unreachable,
+
+            .array => return null,
+            .array_u8_sentinel_0 => return Value.initTag(.zero),
+        };
+    }
+
     /// Returns true if and only if the type is a fixed-width, signed integer.
     pub fn isSignedInt(self: Type) bool {
         return switch (self.tag()) {
@@ -481,6 +645,8 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .array,
@@ -524,6 +690,8 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .array,
@@ -579,6 +747,7 @@ pub const Type = extern union {
     /// Asserts the type is a function.
     pub fn fnParamLen(self: Type) usize {
         return switch (self.tag()) {
+            .fn_noreturn_no_args => 0,
             .fn_naked_noreturn_no_args => 0,
             .fn_ccc_void_no_args => 0,
 
@@ -595,6 +764,7 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
             .array,
             .single_const_pointer,
             .single_const_pointer_to_comptime_int,
@@ -622,6 +792,7 @@ pub const Type = extern union {
     /// given by `fnParamLen`.
     pub fn fnParamTypes(self: Type, types: []Type) void {
         switch (self.tag()) {
+            .fn_noreturn_no_args => return,
             .fn_naked_noreturn_no_args => return,
             .fn_ccc_void_no_args => return,
 
@@ -638,6 +809,7 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
             .array,
             .single_const_pointer,
             .single_const_pointer_to_comptime_int,
@@ -664,6 +836,7 @@ pub const Type = extern union {
     /// Asserts the type is a function.
     pub fn fnReturnType(self: Type) Type {
         return switch (self.tag()) {
+            .fn_noreturn_no_args => Type.initTag(.noreturn),
             .fn_naked_noreturn_no_args => Type.initTag(.noreturn),
             .fn_ccc_void_no_args => Type.initTag(.void),
 
@@ -680,6 +853,7 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
             .array,
             .single_const_pointer,
             .single_const_pointer_to_comptime_int,
@@ -706,6 +880,7 @@ pub const Type = extern union {
     /// Asserts the type is a function.
     pub fn fnCallingConvention(self: Type) std.builtin.CallingConvention {
         return switch (self.tag()) {
+            .fn_noreturn_no_args => .Unspecified,
             .fn_naked_noreturn_no_args => .Naked,
             .fn_ccc_void_no_args => .C,
 
@@ -722,6 +897,51 @@ pub const Type = extern union {
             .comptime_int,
             .comptime_float,
             .noreturn,
+            .@"null",
+            .array,
+            .single_const_pointer,
+            .single_const_pointer_to_comptime_int,
+            .array_u8_sentinel_0,
+            .const_slice_u8,
+            .u8,
+            .i8,
+            .usize,
+            .isize,
+            .c_short,
+            .c_ushort,
+            .c_int,
+            .c_uint,
+            .c_long,
+            .c_ulong,
+            .c_longlong,
+            .c_ulonglong,
+            .int_unsigned,
+            .int_signed,
+            => unreachable,
+        };
+    }
+
+    /// Asserts the type is a function.
+    pub fn fnIsVarArgs(self: Type) bool {
+        return switch (self.tag()) {
+            .fn_noreturn_no_args => false,
+            .fn_naked_noreturn_no_args => false,
+            .fn_ccc_void_no_args => false,
+
+            .f16,
+            .f32,
+            .f64,
+            .f128,
+            .c_longdouble,
+            .c_void,
+            .bool,
+            .void,
+            .type,
+            .anyerror,
+            .comptime_int,
+            .comptime_float,
+            .noreturn,
+            .@"null",
             .array,
             .single_const_pointer,
             .single_const_pointer_to_comptime_int,
@@ -776,6 +996,8 @@ pub const Type = extern union {
             .type,
             .anyerror,
             .noreturn,
+            .@"null",
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .array,
@@ -812,6 +1034,7 @@ pub const Type = extern union {
             .bool,
             .type,
             .anyerror,
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .single_const_pointer_to_comptime_int,
@@ -822,6 +1045,7 @@ pub const Type = extern union {
             .c_void,
             .void,
             .noreturn,
+            .@"null",
             => return true,
 
             .int_unsigned => return ty.cast(Payload.IntUnsigned).?.bits == 0,
@@ -865,6 +1089,7 @@ pub const Type = extern union {
             .bool,
             .type,
             .anyerror,
+            .fn_noreturn_no_args,
             .fn_naked_noreturn_no_args,
             .fn_ccc_void_no_args,
             .single_const_pointer_to_comptime_int,
@@ -873,6 +1098,7 @@ pub const Type = extern union {
             .c_void,
             .void,
             .noreturn,
+            .@"null",
             .int_unsigned,
             .int_signed,
             .array,
@@ -902,11 +1128,11 @@ pub const Type = extern union {
         c_longlong,
         c_ulonglong,
         c_longdouble,
-        c_void,
         f16,
         f32,
         f64,
         f128,
+        c_void,
         bool,
         void,
         type,
@@ -914,6 +1140,8 @@ pub const Type = extern union {
         comptime_int,
         comptime_float,
         noreturn,
+        @"null",
+        fn_noreturn_no_args,
         fn_naked_noreturn_no_args,
         fn_ccc_void_no_args,
         single_const_pointer_to_comptime_int,

src-self-hosted/util.zig

@@ -1,47 +0,0 @@
-const std = @import("std");
-const Target = std.Target;
-const llvm = @import("llvm.zig");
-
-pub fn getDarwinArchString(self: Target) [:0]const u8 {
-    switch (self.cpu.arch) {
-        .aarch64 => return "arm64",
-        .thumb,
-        .arm,
-        => return "arm",
-        .powerpc => return "ppc",
-        .powerpc64 => return "ppc64",
-        .powerpc64le => return "ppc64le",
-        // @tagName should be able to return sentinel terminated slice
-        else => @panic("TODO https://github.com/ziglang/zig/issues/3779"), //return @tagName(arch),
-    }
-}
-
-pub fn llvmTargetFromTriple(triple: [:0]const u8) !*llvm.Target {
-    var result: *llvm.Target = undefined;
-    var err_msg: [*:0]u8 = undefined;
-    if (llvm.GetTargetFromTriple(triple, &result, &err_msg) != 0) {
-        std.debug.warn("triple: {s} error: {s}\n", .{ triple, err_msg });
-        return error.UnsupportedTarget;
-    }
-    return result;
-}
-
-pub fn initializeAllTargets() void {
-    llvm.InitializeAllTargets();
-    llvm.InitializeAllTargetInfos();
-    llvm.InitializeAllTargetMCs();
-    llvm.InitializeAllAsmPrinters();
-    llvm.InitializeAllAsmParsers();
-}
-
-pub fn getLLVMTriple(allocator: *std.mem.Allocator, target: std.Target) ![:0]u8 {
-    var result = try std.ArrayListSentineled(u8, 0).initSize(allocator, 0);
-    defer result.deinit();
-
-    try result.outStream().print(
-        "{}-unknown-{}-{}",
-        .{ @tagName(target.cpu.arch), @tagName(target.os.tag), @tagName(target.abi) },
-    );
-
-    return result.toOwnedSlice();
-}

src-self-hosted/value.zig

@@ -6,10 +6,11 @@ const BigIntConst = std.math.big.int.Const;
 const BigIntMutable = std.math.big.int.Mutable;
 const Target = std.Target;
 const Allocator = std.mem.Allocator;
+const Module = @import("Module.zig");
 
 /// This is the raw data, with no bookkeeping, no memory awareness,
 /// no de-duplication, and no type system awareness.
-/// It's important for this struct to be small.
+/// It's important for this type to be small.
 /// This union takes advantage of the fact that the first page of memory
 /// is unmapped, giving us 4096 possible enum tags that have no payload.
 pub const Value = extern union {
@@ -45,6 +46,8 @@ pub const Value = extern union {
         comptime_int_type,
         comptime_float_type,
         noreturn_type,
+        null_type,
+        fn_noreturn_no_args_type,
         fn_naked_noreturn_no_args_type,
         fn_ccc_void_no_args_type,
         single_const_pointer_to_comptime_int_type,
@@ -64,8 +67,9 @@ pub const Value = extern union {
         int_big_positive,
         int_big_negative,
         function,
-        ref,
         ref_val,
+        decl_ref,
+        elem_ptr,
         bytes,
         repeated, // the value is a value repeated some number of times
 
@@ -136,6 +140,8 @@ pub const Value = extern union {
             .comptime_int_type => return out_stream.writeAll("comptime_int"),
             .comptime_float_type => return out_stream.writeAll("comptime_float"),
             .noreturn_type => return out_stream.writeAll("noreturn"),
+            .null_type => return out_stream.writeAll("@TypeOf(null)"),
+            .fn_noreturn_no_args_type => return out_stream.writeAll("fn() noreturn"),
             .fn_naked_noreturn_no_args_type => return out_stream.writeAll("fn() callconv(.Naked) noreturn"),
             .fn_ccc_void_no_args_type => return out_stream.writeAll("fn() callconv(.C) void"),
             .single_const_pointer_to_comptime_int_type => return out_stream.writeAll("*const comptime_int"),
@@ -153,11 +159,16 @@ pub const Value = extern union {
             .int_big_positive => return out_stream.print("{}", .{val.cast(Payload.IntBigPositive).?.asBigInt()}),
             .int_big_negative => return out_stream.print("{}", .{val.cast(Payload.IntBigNegative).?.asBigInt()}),
             .function => return out_stream.writeAll("(function)"),
-            .ref => return out_stream.writeAll("(ref)"),
             .ref_val => {
-                try out_stream.writeAll("*const ");
-                val = val.cast(Payload.RefVal).?.val;
-                continue;
+                const ref_val = val.cast(Payload.RefVal).?;
+                try out_stream.writeAll("&const ");
+                val = ref_val.val;
+            },
+            .decl_ref => return out_stream.writeAll("(decl ref)"),
+            .elem_ptr => {
+                const elem_ptr = val.cast(Payload.ElemPtr).?;
+                try out_stream.print("&[{}] ", .{elem_ptr.index});
+                val = elem_ptr.array_ptr;
             },
             .bytes => return std.zig.renderStringLiteral(self.cast(Payload.Bytes).?.data, out_stream),
             .repeated => {
@@ -169,10 +180,17 @@ pub const Value = extern union {
 
     /// Asserts that the value is representable as an array of bytes.
     /// Copies the value into a freshly allocated slice of memory, which is owned by the caller.
-    pub fn toAllocatedBytes(self: Value, allocator: *Allocator) Allocator.Error![]u8 {
+    pub fn toAllocatedBytes(self: Value, allocator: *Allocator) ![]u8 {
         if (self.cast(Payload.Bytes)) |bytes| {
             return std.mem.dupe(allocator, u8, bytes.data);
         }
+        if (self.cast(Payload.Repeated)) |repeated| {
+            @panic("TODO implement toAllocatedBytes for this Value tag");
+        }
+        if (self.cast(Payload.DeclRef)) |declref| {
+            const val = try declref.decl.value();
+            return val.toAllocatedBytes(allocator);
+        }
         unreachable;
     }
 
@@ -181,31 +199,33 @@ pub const Value = extern union {
         return switch (self.tag()) {
             .ty => self.cast(Payload.Ty).?.ty,
 
-            .u8_type => Type.initTag(.@"u8"),
-            .i8_type => Type.initTag(.@"i8"),
-            .isize_type => Type.initTag(.@"isize"),
-            .usize_type => Type.initTag(.@"usize"),
-            .c_short_type => Type.initTag(.@"c_short"),
-            .c_ushort_type => Type.initTag(.@"c_ushort"),
-            .c_int_type => Type.initTag(.@"c_int"),
-            .c_uint_type => Type.initTag(.@"c_uint"),
-            .c_long_type => Type.initTag(.@"c_long"),
-            .c_ulong_type => Type.initTag(.@"c_ulong"),
-            .c_longlong_type => Type.initTag(.@"c_longlong"),
-            .c_ulonglong_type => Type.initTag(.@"c_ulonglong"),
-            .c_longdouble_type => Type.initTag(.@"c_longdouble"),
-            .f16_type => Type.initTag(.@"f16"),
-            .f32_type => Type.initTag(.@"f32"),
-            .f64_type => Type.initTag(.@"f64"),
-            .f128_type => Type.initTag(.@"f128"),
-            .c_void_type => Type.initTag(.@"c_void"),
-            .bool_type => Type.initTag(.@"bool"),
-            .void_type => Type.initTag(.@"void"),
-            .type_type => Type.initTag(.@"type"),
-            .anyerror_type => Type.initTag(.@"anyerror"),
-            .comptime_int_type => Type.initTag(.@"comptime_int"),
-            .comptime_float_type => Type.initTag(.@"comptime_float"),
-            .noreturn_type => Type.initTag(.@"noreturn"),
+            .u8_type => Type.initTag(.u8),
+            .i8_type => Type.initTag(.i8),
+            .isize_type => Type.initTag(.isize),
+            .usize_type => Type.initTag(.usize),
+            .c_short_type => Type.initTag(.c_short),
+            .c_ushort_type => Type.initTag(.c_ushort),
+            .c_int_type => Type.initTag(.c_int),
+            .c_uint_type => Type.initTag(.c_uint),
+            .c_long_type => Type.initTag(.c_long),
+            .c_ulong_type => Type.initTag(.c_ulong),
+            .c_longlong_type => Type.initTag(.c_longlong),
+            .c_ulonglong_type => Type.initTag(.c_ulonglong),
+            .c_longdouble_type => Type.initTag(.c_longdouble),
+            .f16_type => Type.initTag(.f16),
+            .f32_type => Type.initTag(.f32),
+            .f64_type => Type.initTag(.f64),
+            .f128_type => Type.initTag(.f128),
+            .c_void_type => Type.initTag(.c_void),
+            .bool_type => Type.initTag(.bool),
+            .void_type => Type.initTag(.void),
+            .type_type => Type.initTag(.type),
+            .anyerror_type => Type.initTag(.anyerror),
+            .comptime_int_type => Type.initTag(.comptime_int),
+            .comptime_float_type => Type.initTag(.comptime_float),
+            .noreturn_type => Type.initTag(.noreturn),
+            .null_type => Type.initTag(.@"null"),
+            .fn_noreturn_no_args_type => Type.initTag(.fn_noreturn_no_args),
             .fn_naked_noreturn_no_args_type => Type.initTag(.fn_naked_noreturn_no_args),
             .fn_ccc_void_no_args_type => Type.initTag(.fn_ccc_void_no_args),
             .single_const_pointer_to_comptime_int_type => Type.initTag(.single_const_pointer_to_comptime_int),
@@ -222,8 +242,9 @@ pub const Value = extern union {
             .int_big_positive,
             .int_big_negative,
             .function,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .repeated,
             => unreachable,
@@ -259,6 +280,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -267,8 +290,9 @@ pub const Value = extern union {
             .bool_false,
             .null_value,
             .function,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .undef,
             .repeated,
@@ -314,6 +338,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -322,8 +348,9 @@ pub const Value = extern union {
             .bool_false,
             .null_value,
             .function,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .undef,
             .repeated,
@@ -370,6 +397,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -378,8 +407,9 @@ pub const Value = extern union {
             .bool_false,
             .null_value,
             .function,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .undef,
             .repeated,
@@ -431,6 +461,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -439,8 +471,9 @@ pub const Value = extern union {
             .bool_false,
             .null_value,
             .function,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .repeated,
             => unreachable,
@@ -521,6 +554,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -529,8 +564,9 @@ pub const Value = extern union {
             .bool_false,
             .null_value,
             .function,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .repeated,
             .undef,
@@ -573,6 +609,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -581,8 +619,9 @@ pub const Value = extern union {
             .bool_false,
             .null_value,
             .function,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .repeated,
             .undef,
@@ -636,7 +675,8 @@ pub const Value = extern union {
     }
 
     /// Asserts the value is a pointer and dereferences it.
-    pub fn pointerDeref(self: Value) Value {
+    /// Returns error.AnalysisFail if the pointer points to a Decl that failed semantic analysis.
+    pub fn pointerDeref(self: Value, allocator: *Allocator) error{ AnalysisFail, OutOfMemory }!Value {
         return switch (self.tag()) {
             .ty,
             .u8_type,
@@ -664,6 +704,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -683,14 +725,19 @@ pub const Value = extern union {
             => unreachable,
 
             .the_one_possible_value => Value.initTag(.the_one_possible_value),
-            .ref => self.cast(Payload.Ref).?.cell.contents,
             .ref_val => self.cast(Payload.RefVal).?.val,
+            .decl_ref => self.cast(Payload.DeclRef).?.decl.value(),
+            .elem_ptr => {
+                const elem_ptr = self.cast(Payload.ElemPtr).?;
+                const array_val = try elem_ptr.array_ptr.pointerDeref(allocator);
+                return array_val.elemValue(allocator, elem_ptr.index);
+            },
         };
     }
 
     /// Asserts the value is a single-item pointer to an array, or an array,
     /// or an unknown-length pointer, and returns the element value at the index.
-    pub fn elemValueAt(self: Value, allocator: *Allocator, index: usize) Allocator.Error!Value {
+    pub fn elemValue(self: Value, allocator: *Allocator, index: usize) error{OutOfMemory}!Value {
         switch (self.tag()) {
             .ty,
             .u8_type,
@@ -718,6 +765,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -733,13 +782,13 @@ pub const Value = extern union {
             .int_big_positive,
             .int_big_negative,
             .undef,
+            .elem_ptr,
+            .ref_val,
+            .decl_ref,
             => unreachable,
 
-            .ref => @panic("TODO figure out how MemoryCell works"),
-            .ref_val => @panic("TODO figure out how MemoryCell works"),
-
             .bytes => {
-                const int_payload = try allocator.create(Value.Payload.Int_u64);
+                const int_payload = try allocator.create(Payload.Int_u64);
                 int_payload.* = .{ .int = self.cast(Payload.Bytes).?.data[index] };
                 return Value.initPayload(&int_payload.base);
             },
@@ -749,6 +798,17 @@ pub const Value = extern union {
         }
     }
 
+    /// Returns a pointer to the element value at the index.
+    pub fn elemPtr(self: Value, allocator: *Allocator, index: usize) !Value {
+        const payload = try allocator.create(Payload.ElemPtr);
+        if (self.cast(Payload.ElemPtr)) |elem_ptr| {
+            payload.* = .{ .array_ptr = elem_ptr.array_ptr, .index = elem_ptr.index + index };
+        } else {
+            payload.* = .{ .array_ptr = self, .index = index };
+        }
+        return Value.initPayload(&payload.base);
+    }
+
     pub fn isUndef(self: Value) bool {
         return self.tag() == .undef;
     }
@@ -783,6 +843,8 @@ pub const Value = extern union {
             .comptime_int_type,
             .comptime_float_type,
             .noreturn_type,
+            .null_type,
+            .fn_noreturn_no_args_type,
             .fn_naked_noreturn_no_args_type,
             .fn_ccc_void_no_args_type,
             .single_const_pointer_to_comptime_int_type,
@@ -796,8 +858,9 @@ pub const Value = extern union {
             .int_i64,
             .int_big_positive,
             .int_big_negative,
-            .ref,
             .ref_val,
+            .decl_ref,
+            .elem_ptr,
             .bytes,
             .repeated,
             => false,
@@ -841,8 +904,7 @@ pub const Value = extern union {
 
         pub const Function = struct {
             base: Payload = Payload{ .tag = .function },
-            /// Index into the `fns` array of the `ir.Module`
-            index: usize,
+            func: *Module.Fn,
         };
 
         pub const ArraySentinel0_u8_Type = struct {
@@ -855,16 +917,24 @@ pub const Value = extern union {
             elem_type: *Type,
         };
 
-        pub const Ref = struct {
-            base: Payload = Payload{ .tag = .ref },
-            cell: *MemoryCell,
-        };
-
+        /// Represents a pointer to another immutable value.
         pub const RefVal = struct {
             base: Payload = Payload{ .tag = .ref_val },
             val: Value,
         };
 
+        /// Represents a pointer to a decl, not the value of the decl.
+        pub const DeclRef = struct {
+            base: Payload = Payload{ .tag = .decl_ref },
+            decl: *Module.Decl,
+        };
+
+        pub const ElemPtr = struct {
+            base: Payload = Payload{ .tag = .elem_ptr },
+            array_ptr: Value,
+            index: usize,
+        };
+
         pub const Bytes = struct {
             base: Payload = Payload{ .tag = .bytes },
             data: []const u8,
@@ -890,29 +960,3 @@ pub const Value = extern union {
         limbs: [(@sizeOf(u64) / @sizeOf(std.math.big.Limb)) + 1]std.math.big.Limb,
     };
 };
-
-/// This is the heart of resource management of the Zig compiler. The Zig compiler uses
-/// stop-the-world mark-and-sweep garbage collection during compilation to manage the resources
-/// associated with evaluating compile-time code and semantic analysis. Each `MemoryCell` represents
-/// a root.
-pub const MemoryCell = struct {
-    parent: Parent,
-    contents: Value,
-
-    pub const Parent = union(enum) {
-        none,
-        struct_field: struct {
-            struct_base: *MemoryCell,
-            field_index: usize,
-        },
-        array_elem: struct {
-            array_base: *MemoryCell,
-            elem_index: usize,
-        },
-        union_field: *MemoryCell,
-        err_union_code: *MemoryCell,
-        err_union_payload: *MemoryCell,
-        optional_payload: *MemoryCell,
-        optional_flag: *MemoryCell,
-    };
-};

src-self-hosted/visib.zig

@@ -1,4 +0,0 @@
-pub const Visib = enum {
-    Private,
-    Pub,
-};

src-self-hosted/zir.zig

@@ -6,9 +6,11 @@ const Allocator = std.mem.Allocator;
 const assert = std.debug.assert;
 const BigIntConst = std.math.big.int.Const;
 const BigIntMutable = std.math.big.int.Mutable;
-const Type = @import("../type.zig").Type;
-const Value = @import("../value.zig").Value;
-const ir = @import("../ir.zig");
+const Type = @import("type.zig").Type;
+const Value = @import("value.zig").Value;
+const TypedValue = @import("TypedValue.zig");
+const ir = @import("ir.zig");
+const IrModule = @import("Module.zig");
 
 /// These are instructions that correspond to the ZIR text format. See `ir.Inst` for
 /// in-memory, analyzed instructions with types and values.
@@ -16,10 +18,18 @@ pub const Inst = struct {
     tag: Tag,
     /// Byte offset into the source.
     src: usize,
+    name: []const u8,
+
+    /// Slice into the source of the part after the = and before the next instruction.
+    contents: []const u8 = &[0]u8{},
 
     /// These names are used directly as the instruction names in the text format.
     pub const Tag = enum {
         breakpoint,
+        call,
+        /// Represents a reference to a global decl by name.
+        /// The syntax `@foo` is equivalent to `declref("foo")`.
+        declref,
         str,
         int,
         ptrtoint,
@@ -32,6 +42,7 @@ pub const Inst = struct {
         @"fn",
         @"export",
         primitive,
+        ref,
         fntype,
         intcast,
         bitcast,
@@ -46,6 +57,8 @@ pub const Inst = struct {
     pub fn TagToType(tag: Tag) type {
         return switch (tag) {
             .breakpoint => Breakpoint,
+            .call => Call,
+            .declref => DeclRef,
             .str => Str,
             .int => Int,
             .ptrtoint => PtrToInt,
@@ -58,6 +71,7 @@ pub const Inst = struct {
             .@"fn" => Fn,
             .@"export" => Export,
             .primitive => Primitive,
+            .ref => Ref,
             .fntype => FnType,
             .intcast => IntCast,
             .bitcast => BitCast,
@@ -85,6 +99,29 @@ pub const Inst = struct {
         kw_args: struct {},
     };
 
+    pub const Call = struct {
+        pub const base_tag = Tag.call;
+        base: Inst,
+
+        positionals: struct {
+            func: *Inst,
+            args: []*Inst,
+        },
+        kw_args: struct {
+            modifier: std.builtin.CallOptions.Modifier = .auto,
+        },
+    };
+
+    pub const DeclRef = struct {
+        pub const base_tag = Tag.declref;
+        base: Inst,
+
+        positionals: struct {
+            name: *Inst,
+        },
+        kw_args: struct {},
+    };
+
     pub const Str = struct {
         pub const base_tag = Tag.str;
         base: Inst,
@@ -202,6 +239,16 @@ pub const Inst = struct {
         kw_args: struct {},
     };
 
+    pub const Ref = struct {
+        pub const base_tag = Tag.ref;
+        base: Inst,
+
+        positionals: struct {
+            operand: *Inst,
+        },
+        kw_args: struct {},
+    };
+
     pub const Primitive = struct {
         pub const base_tag = Tag.primitive;
         base: Inst,
@@ -212,55 +259,55 @@ pub const Inst = struct {
         kw_args: struct {},
 
         pub const BuiltinType = enum {
-            @"isize",
-            @"usize",
-            @"c_short",
-            @"c_ushort",
-            @"c_int",
-            @"c_uint",
-            @"c_long",
-            @"c_ulong",
-            @"c_longlong",
-            @"c_ulonglong",
-            @"c_longdouble",
-            @"c_void",
-            @"f16",
-            @"f32",
-            @"f64",
-            @"f128",
-            @"bool",
-            @"void",
-            @"noreturn",
-            @"type",
-            @"anyerror",
-            @"comptime_int",
-            @"comptime_float",
+            isize,
+            usize,
+            c_short,
+            c_ushort,
+            c_int,
+            c_uint,
+            c_long,
+            c_ulong,
+            c_longlong,
+            c_ulonglong,
+            c_longdouble,
+            c_void,
+            f16,
+            f32,
+            f64,
+            f128,
+            bool,
+            void,
+            noreturn,
+            type,
+            anyerror,
+            comptime_int,
+            comptime_float,
 
             pub fn toType(self: BuiltinType) Type {
                 return switch (self) {
-                    .@"isize" => Type.initTag(.@"isize"),
-                    .@"usize" => Type.initTag(.@"usize"),
-                    .@"c_short" => Type.initTag(.@"c_short"),
-                    .@"c_ushort" => Type.initTag(.@"c_ushort"),
-                    .@"c_int" => Type.initTag(.@"c_int"),
-                    .@"c_uint" => Type.initTag(.@"c_uint"),
-                    .@"c_long" => Type.initTag(.@"c_long"),
-                    .@"c_ulong" => Type.initTag(.@"c_ulong"),
-                    .@"c_longlong" => Type.initTag(.@"c_longlong"),
-                    .@"c_ulonglong" => Type.initTag(.@"c_ulonglong"),
-                    .@"c_longdouble" => Type.initTag(.@"c_longdouble"),
-                    .@"c_void" => Type.initTag(.@"c_void"),
-                    .@"f16" => Type.initTag(.@"f16"),
-                    .@"f32" => Type.initTag(.@"f32"),
-                    .@"f64" => Type.initTag(.@"f64"),
-                    .@"f128" => Type.initTag(.@"f128"),
-                    .@"bool" => Type.initTag(.@"bool"),
-                    .@"void" => Type.initTag(.@"void"),
-                    .@"noreturn" => Type.initTag(.@"noreturn"),
-                    .@"type" => Type.initTag(.@"type"),
-                    .@"anyerror" => Type.initTag(.@"anyerror"),
-                    .@"comptime_int" => Type.initTag(.@"comptime_int"),
-                    .@"comptime_float" => Type.initTag(.@"comptime_float"),
+                    .isize => Type.initTag(.isize),
+                    .usize => Type.initTag(.usize),
+                    .c_short => Type.initTag(.c_short),
+                    .c_ushort => Type.initTag(.c_ushort),
+                    .c_int => Type.initTag(.c_int),
+                    .c_uint => Type.initTag(.c_uint),
+                    .c_long => Type.initTag(.c_long),
+                    .c_ulong => Type.initTag(.c_ulong),
+                    .c_longlong => Type.initTag(.c_longlong),
+                    .c_ulonglong => Type.initTag(.c_ulonglong),
+                    .c_longdouble => Type.initTag(.c_longdouble),
+                    .c_void => Type.initTag(.c_void),
+                    .f16 => Type.initTag(.f16),
+                    .f32 => Type.initTag(.f32),
+                    .f64 => Type.initTag(.f64),
+                    .f128 => Type.initTag(.f128),
+                    .bool => Type.initTag(.bool),
+                    .void => Type.initTag(.void),
+                    .noreturn => Type.initTag(.noreturn),
+                    .type => Type.initTag(.type),
+                    .anyerror => Type.initTag(.anyerror),
+                    .comptime_int => Type.initTag(.comptime_int),
+                    .comptime_float => Type.initTag(.comptime_float),
                 };
             }
         };
@@ -375,8 +422,8 @@ pub const ErrorMsg = struct {
 
 pub const Module = struct {
     decls: []*Inst,
-    errors: []ErrorMsg,
     arena: std.heap.ArenaAllocator,
+    error_msg: ?ErrorMsg = null,
 
     pub const Body = struct {
         instructions: []*Inst,
@@ -384,7 +431,6 @@ pub const Module = struct {
 
     pub fn deinit(self: *Module, allocator: *Allocator) void {
         allocator.free(self.decls);
-        allocator.free(self.errors);
         self.arena.deinit();
         self.* = undefined;
     }
@@ -431,6 +477,8 @@ pub const Module = struct {
         // TODO I tried implementing this with an inline for loop and hit a compiler bug
         switch (decl.tag) {
             .breakpoint => return self.writeInstToStreamGeneric(stream, .breakpoint, decl, inst_table),
+            .call => return self.writeInstToStreamGeneric(stream, .call, decl, inst_table),
+            .declref => return self.writeInstToStreamGeneric(stream, .declref, decl, inst_table),
             .str => return self.writeInstToStreamGeneric(stream, .str, decl, inst_table),
             .int => return self.writeInstToStreamGeneric(stream, .int, decl, inst_table),
             .ptrtoint => return self.writeInstToStreamGeneric(stream, .ptrtoint, decl, inst_table),
@@ -442,6 +490,7 @@ pub const Module = struct {
             .@"return" => return self.writeInstToStreamGeneric(stream, .@"return", decl, inst_table),
             .@"fn" => return self.writeInstToStreamGeneric(stream, .@"fn", decl, inst_table),
             .@"export" => return self.writeInstToStreamGeneric(stream, .@"export", decl, inst_table),
+            .ref => return self.writeInstToStreamGeneric(stream, .ref, decl, inst_table),
             .primitive => return self.writeInstToStreamGeneric(stream, .primitive, decl, inst_table),
             .fntype => return self.writeInstToStreamGeneric(stream, .fntype, decl, inst_table),
             .intcast => return self.writeInstToStreamGeneric(stream, .intcast, decl, inst_table),
@@ -543,22 +592,23 @@ pub fn parse(allocator: *Allocator, source: [:0]const u8) Allocator.Error!Module
         .arena = std.heap.ArenaAllocator.init(allocator),
         .i = 0,
         .source = source,
-        .decls = std.ArrayList(*Inst).init(allocator),
-        .errors = std.ArrayList(ErrorMsg).init(allocator),
         .global_name_map = &global_name_map,
+        .decls = .{},
+        .unnamed_index = 0,
     };
     errdefer parser.arena.deinit();
 
     parser.parseRoot() catch |err| switch (err) {
         error.ParseFailure => {
-            assert(parser.errors.items.len != 0);
+            assert(parser.error_msg != null);
         },
         else => |e| return e,
     };
+
     return Module{
-        .decls = parser.decls.toOwnedSlice(),
-        .errors = parser.errors.toOwnedSlice(),
+        .decls = parser.decls.toOwnedSlice(allocator),
         .arena = parser.arena,
+        .error_msg = parser.error_msg,
     };
 }
 
@@ -567,9 +617,10 @@ const Parser = struct {
     arena: std.heap.ArenaAllocator,
     i: usize,
     source: [:0]const u8,
-    errors: std.ArrayList(ErrorMsg),
-    decls: std.ArrayList(*Inst),
+    decls: std.ArrayListUnmanaged(*Inst),
     global_name_map: *std.StringHashMap(usize),
+    error_msg: ?ErrorMsg = null,
+    unnamed_index: usize,
 
     const Body = struct {
         instructions: std.ArrayList(*Inst),
@@ -595,7 +646,7 @@ const Parser = struct {
                 skipSpace(self);
                 try requireEatBytes(self, "=");
                 skipSpace(self);
-                const inst = try parseInstruction(self, &body_context);
+                const inst = try parseInstruction(self, &body_context, ident);
                 const ident_index = body_context.instructions.items.len;
                 if (try body_context.name_map.put(ident, ident_index)) |_| {
                     return self.fail("redefinition of identifier '{}'", .{ident});
@@ -681,12 +732,12 @@ const Parser = struct {
                     skipSpace(self);
                     try requireEatBytes(self, "=");
                     skipSpace(self);
-                    const inst = try parseInstruction(self, null);
+                    const inst = try parseInstruction(self, null, ident);
                     const ident_index = self.decls.items.len;
                     if (try self.global_name_map.put(ident, ident_index)) |_| {
                         return self.fail("redefinition of identifier '{}'", .{ident});
                     }
-                    try self.decls.append(inst);
+                    try self.decls.append(self.allocator, inst);
                 },
                 ' ', '\n' => self.i += 1,
                 0 => break,
@@ -743,20 +794,20 @@ const Parser = struct {
 
     fn fail(self: *Parser, comptime format: []const u8, args: var) InnerError {
         @setCold(true);
-        const msg = try std.fmt.allocPrint(&self.arena.allocator, format, args);
-        (try self.errors.addOne()).* = .{
+        self.error_msg = ErrorMsg{
             .byte_offset = self.i,
-            .msg = msg,
+            .msg = try std.fmt.allocPrint(&self.arena.allocator, format, args),
         };
         return error.ParseFailure;
     }
 
-    fn parseInstruction(self: *Parser, body_ctx: ?*Body) InnerError!*Inst {
+    fn parseInstruction(self: *Parser, body_ctx: ?*Body, name: []const u8) InnerError!*Inst {
+        const contents_start = self.i;
         const fn_name = try skipToAndOver(self, '(');
         inline for (@typeInfo(Inst.Tag).Enum.fields) |field| {
             if (mem.eql(u8, field.name, fn_name)) {
                 const tag = @field(Inst.Tag, field.name);
-                return parseInstructionGeneric(self, field.name, Inst.TagToType(tag), body_ctx);
+                return parseInstructionGeneric(self, field.name, Inst.TagToType(tag), body_ctx, name, contents_start);
             }
         }
         return self.fail("unknown instruction '{}'", .{fn_name});
@@ -767,9 +818,12 @@ const Parser = struct {
         comptime fn_name: []const u8,
         comptime InstType: type,
         body_ctx: ?*Body,
-    ) !*Inst {
+        inst_name: []const u8,
+        contents_start: usize,
+    ) InnerError!*Inst {
         const inst_specific = try self.arena.allocator.create(InstType);
         inst_specific.base = .{
+            .name = inst_name,
             .src = self.i,
             .tag = InstType.base_tag,
         };
@@ -819,6 +873,8 @@ const Parser = struct {
         }
         try requireEatBytes(self, ")");
 
+        inst_specific.base.contents = self.source[contents_start..self.i];
+
         return &inst_specific.base;
     }
 
@@ -893,8 +949,33 @@ const Parser = struct {
         const ident = self.source[name_start..self.i];
         const kv = map.get(ident) orelse {
             const bad_name = self.source[name_start - 1 .. self.i];
-            self.i = name_start - 1;
-            return self.fail("unrecognized identifier: {}", .{bad_name});
+            const src = name_start - 1;
+            if (local_ref) {
+                self.i = src;
+                return self.fail("unrecognized identifier: {}", .{bad_name});
+            } else {
+                const name = try self.arena.allocator.create(Inst.Str);
+                name.* = .{
+                    .base = .{
+                        .name = try self.generateName(),
+                        .src = src,
+                        .tag = Inst.Str.base_tag,
+                    },
+                    .positionals = .{ .bytes = ident },
+                    .kw_args = .{},
+                };
+                const declref = try self.arena.allocator.create(Inst.DeclRef);
+                declref.* = .{
+                    .base = .{
+                        .name = try self.generateName(),
+                        .src = src,
+                        .tag = Inst.DeclRef.base_tag,
+                    },
+                    .positionals = .{ .name = &name.base },
+                    .kw_args = .{},
+                };
+                return &declref.base;
+            }
         };
         if (local_ref) {
             return body_ctx.?.instructions.items[kv.value];
@@ -902,50 +983,64 @@ const Parser = struct {
             return self.decls.items[kv.value];
         }
     }
+
+    fn generateName(self: *Parser) ![]u8 {
+        const result = try std.fmt.allocPrint(&self.arena.allocator, "unnamed${}", .{self.unnamed_index});
+        self.unnamed_index += 1;
+        return result;
+    }
 };
 
-pub fn emit_zir(allocator: *Allocator, old_module: ir.Module) !Module {
+pub fn emit(allocator: *Allocator, old_module: IrModule) !Module {
     var ctx: EmitZIR = .{
         .allocator = allocator,
-        .decls = std.ArrayList(*Inst).init(allocator),
+        .decls = .{},
         .decl_table = std.AutoHashMap(*ir.Inst, *Inst).init(allocator),
         .arena = std.heap.ArenaAllocator.init(allocator),
         .old_module = &old_module,
     };
-    defer ctx.decls.deinit();
+    defer ctx.decls.deinit(allocator);
     defer ctx.decl_table.deinit();
     errdefer ctx.arena.deinit();
 
     try ctx.emit();
 
     return Module{
-        .decls = ctx.decls.toOwnedSlice(),
+        .decls = ctx.decls.toOwnedSlice(allocator),
         .arena = ctx.arena,
-        .errors = &[0]ErrorMsg{},
     };
 }
 
 const EmitZIR = struct {
     allocator: *Allocator,
     arena: std.heap.ArenaAllocator,
-    old_module: *const ir.Module,
-    decls: std.ArrayList(*Inst),
+    old_module: *const IrModule,
+    decls: std.ArrayListUnmanaged(*Inst),
     decl_table: std.AutoHashMap(*ir.Inst, *Inst),
 
     fn emit(self: *EmitZIR) !void {
-        for (self.old_module.exports) |module_export| {
-            const export_value = try self.emitTypedValue(module_export.src, module_export.typed_value);
-            const symbol_name = try self.emitStringLiteral(module_export.src, module_export.name);
-            const export_inst = try self.arena.allocator.create(Inst.Export);
-            export_inst.* = .{
-                .base = .{ .src = module_export.src, .tag = Inst.Export.base_tag },
-                .positionals = .{
-                    .symbol_name = symbol_name,
-                    .value = export_value,
-                },
-                .kw_args = .{},
-            };
-            try self.decls.append(&export_inst.base);
+        var it = self.old_module.decl_exports.iterator();
+        while (it.next()) |kv| {
+            const decl = kv.key;
+            const exports = kv.value;
+            const export_value = try self.emitTypedValue(decl.src, decl.typed_value.most_recent.typed_value);
+            for (exports) |module_export| {
+                const symbol_name = try self.emitStringLiteral(module_export.src, module_export.options.name);
+                const export_inst = try self.arena.allocator.create(Inst.Export);
+                export_inst.* = .{
+                    .base = .{
+                        .name = try self.autoName(),
+                        .src = module_export.src,
+                        .tag = Inst.Export.base_tag,
+                    },
+                    .positionals = .{
+                        .symbol_name = symbol_name,
+                        .value = export_value,
+                    },
+                    .kw_args = .{},
+                };
+                try self.decls.append(self.allocator, &export_inst.base);
+            }
         }
     }
 
@@ -966,17 +1061,22 @@ const EmitZIR = struct {
         const big_int_space = try self.arena.allocator.create(Value.BigIntSpace);
         const int_inst = try self.arena.allocator.create(Inst.Int);
         int_inst.* = .{
-            .base = .{ .src = src, .tag = Inst.Int.base_tag },
+            .base = .{
+                .name = try self.autoName(),
+                .src = src,
+                .tag = Inst.Int.base_tag,
+            },
             .positionals = .{
                 .int = val.toBigInt(big_int_space),
             },
             .kw_args = .{},
         };
-        try self.decls.append(&int_inst.base);
+        try self.decls.append(self.allocator, &int_inst.base);
         return &int_inst.base;
     }
 
-    fn emitTypedValue(self: *EmitZIR, src: usize, typed_value: ir.TypedValue) Allocator.Error!*Inst {
+    fn emitTypedValue(self: *EmitZIR, src: usize, typed_value: TypedValue) Allocator.Error!*Inst {
+        const allocator = &self.arena.allocator;
         switch (typed_value.ty.zigTypeTag()) {
             .Pointer => {
                 const ptr_elem_type = typed_value.ty.elemType();
@@ -988,7 +1088,10 @@ const EmitZIR = struct {
                         //    ptr_elem_type.hasSentinel(Value.initTag(.zero)))
                         //{
                         //}
-                        const bytes = try typed_value.val.toAllocatedBytes(&self.arena.allocator);
+                        const bytes = typed_value.val.toAllocatedBytes(allocator) catch |err| switch (err) {
+                            error.AnalysisFail => unreachable,
+                            else => |e| return e,
+                        };
                         return self.emitStringLiteral(src, bytes);
                     },
                     else => |t| std.debug.panic("TODO implement emitTypedValue for pointer to {}", .{@tagName(t)}),
@@ -998,14 +1101,18 @@ const EmitZIR = struct {
             .Int => {
                 const as_inst = try self.arena.allocator.create(Inst.As);
                 as_inst.* = .{
-                    .base = .{ .src = src, .tag = Inst.As.base_tag },
+                    .base = .{
+                        .name = try self.autoName(),
+                        .src = src,
+                        .tag = Inst.As.base_tag,
+                    },
                     .positionals = .{
                         .dest_type = try self.emitType(src, typed_value.ty),
                         .value = try self.emitComptimeIntVal(src, typed_value.val),
                     },
                     .kw_args = .{},
                 };
-                try self.decls.append(&as_inst.base);
+                try self.decls.append(self.allocator, &as_inst.base);
 
                 return &as_inst.base;
             },
@@ -1014,8 +1121,7 @@ const EmitZIR = struct {
                 return self.emitType(src, ty);
             },
             .Fn => {
-                const index = typed_value.val.cast(Value.Payload.Function).?.index;
-                const module_fn = self.old_module.fns[index];
+                const module_fn = typed_value.val.cast(Value.Payload.Function).?.func;
 
                 var inst_table = std.AutoHashMap(*ir.Inst, *Inst).init(self.allocator);
                 defer inst_table.deinit();
@@ -1023,7 +1129,7 @@ const EmitZIR = struct {
                 var instructions = std.ArrayList(*Inst).init(self.allocator);
                 defer instructions.deinit();
 
-                try self.emitBody(module_fn.body, &inst_table, &instructions);
+                try self.emitBody(module_fn.analysis.success, &inst_table, &instructions);
 
                 const fn_type = try self.emitType(src, module_fn.fn_type);
 
@@ -1032,14 +1138,18 @@ const EmitZIR = struct {
 
                 const fn_inst = try self.arena.allocator.create(Inst.Fn);
                 fn_inst.* = .{
-                    .base = .{ .src = src, .tag = Inst.Fn.base_tag },
+                    .base = .{
+                        .name = try self.autoName(),
+                        .src = src,
+                        .tag = Inst.Fn.base_tag,
+                    },
                     .positionals = .{
                         .fn_type = fn_type,
                         .body = .{ .instructions = arena_instrs },
                     },
                     .kw_args = .{},
                 };
-                try self.decls.append(&fn_inst.base);
+                try self.decls.append(self.allocator, &fn_inst.base);
                 return &fn_inst.base;
             },
             else => |t| std.debug.panic("TODO implement emitTypedValue for {}", .{@tagName(t)}),
@@ -1049,7 +1159,11 @@ const EmitZIR = struct {
     fn emitTrivial(self: *EmitZIR, src: usize, comptime T: type) Allocator.Error!*Inst {
         const new_inst = try self.arena.allocator.create(T);
         new_inst.* = .{
-            .base = .{ .src = src, .tag = T.base_tag },
+            .base = .{
+                .name = try self.autoName(),
+                .src = src,
+                .tag = T.base_tag,
+            },
             .positionals = .{},
             .kw_args = .{},
         };
@@ -1058,13 +1172,35 @@ const EmitZIR = struct {
 
     fn emitBody(
         self: *EmitZIR,
-        body: ir.Module.Body,
+        body: IrModule.Body,
         inst_table: *std.AutoHashMap(*ir.Inst, *Inst),
         instructions: *std.ArrayList(*Inst),
     ) Allocator.Error!void {
         for (body.instructions) |inst| {
             const new_inst = switch (inst.tag) {
                 .breakpoint => try self.emitTrivial(inst.src, Inst.Breakpoint),
+                .call => blk: {
+                    const old_inst = inst.cast(ir.Inst.Call).?;
+                    const new_inst = try self.arena.allocator.create(Inst.Call);
+
+                    const args = try self.arena.allocator.alloc(*Inst, old_inst.args.args.len);
+                    for (args) |*elem, i| {
+                        elem.* = try self.resolveInst(inst_table, old_inst.args.args[i]);
+                    }
+                    new_inst.* = .{
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.Call.base_tag,
+                        },
+                        .positionals = .{
+                            .func = try self.resolveInst(inst_table, old_inst.args.func),
+                            .args = args,
+                        },
+                        .kw_args = .{},
+                    };
+                    break :blk &new_inst.base;
+                },
                 .unreach => try self.emitTrivial(inst.src, Inst.Unreachable),
                 .ret => try self.emitTrivial(inst.src, Inst.Return),
                 .constant => unreachable, // excluded from function bodies
@@ -1088,7 +1224,11 @@ const EmitZIR = struct {
                     }
 
                     new_inst.* = .{
-                        .base = .{ .src = inst.src, .tag = Inst.Asm.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.Asm.base_tag,
+                        },
                         .positionals = .{
                             .asm_source = try self.emitStringLiteral(inst.src, old_inst.args.asm_source),
                             .return_type = try self.emitType(inst.src, inst.ty),
@@ -1110,7 +1250,11 @@ const EmitZIR = struct {
                     const old_inst = inst.cast(ir.Inst.PtrToInt).?;
                     const new_inst = try self.arena.allocator.create(Inst.PtrToInt);
                     new_inst.* = .{
-                        .base = .{ .src = inst.src, .tag = Inst.PtrToInt.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.PtrToInt.base_tag,
+                        },
                         .positionals = .{
                             .ptr = try self.resolveInst(inst_table, old_inst.args.ptr),
                         },
@@ -1122,7 +1266,11 @@ const EmitZIR = struct {
                     const old_inst = inst.cast(ir.Inst.BitCast).?;
                     const new_inst = try self.arena.allocator.create(Inst.BitCast);
                     new_inst.* = .{
-                        .base = .{ .src = inst.src, .tag = Inst.BitCast.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.BitCast.base_tag,
+                        },
                         .positionals = .{
                             .dest_type = try self.emitType(inst.src, inst.ty),
                             .operand = try self.resolveInst(inst_table, old_inst.args.operand),
@@ -1135,7 +1283,11 @@ const EmitZIR = struct {
                     const old_inst = inst.cast(ir.Inst.Cmp).?;
                     const new_inst = try self.arena.allocator.create(Inst.Cmp);
                     new_inst.* = .{
-                        .base = .{ .src = inst.src, .tag = Inst.Cmp.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.Cmp.base_tag,
+                        },
                         .positionals = .{
                             .lhs = try self.resolveInst(inst_table, old_inst.args.lhs),
                             .rhs = try self.resolveInst(inst_table, old_inst.args.rhs),
@@ -1159,7 +1311,11 @@ const EmitZIR = struct {
 
                     const new_inst = try self.arena.allocator.create(Inst.CondBr);
                     new_inst.* = .{
-                        .base = .{ .src = inst.src, .tag = Inst.CondBr.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.CondBr.base_tag,
+                        },
                         .positionals = .{
                             .condition = try self.resolveInst(inst_table, old_inst.args.condition),
                             .true_body = .{ .instructions = true_body.toOwnedSlice() },
@@ -1173,7 +1329,11 @@ const EmitZIR = struct {
                     const old_inst = inst.cast(ir.Inst.IsNull).?;
                     const new_inst = try self.arena.allocator.create(Inst.IsNull);
                     new_inst.* = .{
-                        .base = .{ .src = inst.src, .tag = Inst.IsNull.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.IsNull.base_tag,
+                        },
                         .positionals = .{
                             .operand = try self.resolveInst(inst_table, old_inst.args.operand),
                         },
@@ -1185,7 +1345,11 @@ const EmitZIR = struct {
                     const old_inst = inst.cast(ir.Inst.IsNonNull).?;
                     const new_inst = try self.arena.allocator.create(Inst.IsNonNull);
                     new_inst.* = .{
-                        .base = .{ .src = inst.src, .tag = Inst.IsNonNull.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = inst.src,
+                            .tag = Inst.IsNonNull.base_tag,
+                        },
                         .positionals = .{
                             .operand = try self.resolveInst(inst_table, old_inst.args.operand),
                         },
@@ -1237,7 +1401,11 @@ const EmitZIR = struct {
 
                     const fntype_inst = try self.arena.allocator.create(Inst.FnType);
                     fntype_inst.* = .{
-                        .base = .{ .src = src, .tag = Inst.FnType.base_tag },
+                        .base = .{
+                            .name = try self.autoName(),
+                            .src = src,
+                            .tag = Inst.FnType.base_tag,
+                        },
                         .positionals = .{
                             .param_types = emitted_params,
                             .return_type = try self.emitType(src, ty.fnReturnType()),
@@ -1246,7 +1414,7 @@ const EmitZIR = struct {
                             .cc = ty.fnCallingConvention(),
                         },
                     };
-                    try self.decls.append(&fntype_inst.base);
+                    try self.decls.append(self.allocator, &fntype_inst.base);
                     return &fntype_inst.base;
                 },
                 else => std.debug.panic("TODO implement emitType for {}", .{ty}),
@@ -1254,29 +1422,56 @@ const EmitZIR = struct {
         }
     }
 
+    fn autoName(self: *EmitZIR) ![]u8 {
+        return std.fmt.allocPrint(&self.arena.allocator, "{}", .{self.decls.items.len});
+    }
+
     fn emitPrimitiveType(self: *EmitZIR, src: usize, tag: Inst.Primitive.BuiltinType) !*Inst {
         const primitive_inst = try self.arena.allocator.create(Inst.Primitive);
         primitive_inst.* = .{
-            .base = .{ .src = src, .tag = Inst.Primitive.base_tag },
+            .base = .{
+                .name = try self.autoName(),
+                .src = src,
+                .tag = Inst.Primitive.base_tag,
+            },
             .positionals = .{
                 .tag = tag,
             },
             .kw_args = .{},
         };
-        try self.decls.append(&primitive_inst.base);
+        try self.decls.append(self.allocator, &primitive_inst.base);
         return &primitive_inst.base;
     }
 
     fn emitStringLiteral(self: *EmitZIR, src: usize, str: []const u8) !*Inst {
         const str_inst = try self.arena.allocator.create(Inst.Str);
         str_inst.* = .{
-            .base = .{ .src = src, .tag = Inst.Str.base_tag },
+            .base = .{
+                .name = try self.autoName(),
+                .src = src,
+                .tag = Inst.Str.base_tag,
+            },
             .positionals = .{
                 .bytes = str,
             },
             .kw_args = .{},
         };
-        try self.decls.append(&str_inst.base);
-        return &str_inst.base;
+        try self.decls.append(self.allocator, &str_inst.base);
+
+        const ref_inst = try self.arena.allocator.create(Inst.Ref);
+        ref_inst.* = .{
+            .base = .{
+                .name = try self.autoName(),
+                .src = src,
+                .tag = Inst.Ref.base_tag,
+            },
+            .positionals = .{
+                .operand = &str_inst.base,
+            },
+            .kw_args = .{},
+        };
+        try self.decls.append(self.allocator, &ref_inst.base);
+
+        return &ref_inst.base;
     }
 };

src/codegen.cpp

@@ -1794,6 +1794,16 @@ static LLVMValueRef ir_llvm_value(CodeGen *g, IrInstGen *instruction) {
 }
 
 void codegen_report_errors_and_exit(CodeGen *g) {
+    // Clear progress indicator before printing errors
+    if (g->sub_progress_node != nullptr) {
+        stage2_progress_end(g->sub_progress_node);
+        g->sub_progress_node = nullptr;
+    }
+    if (g->main_progress_node != nullptr) {
+        stage2_progress_end(g->main_progress_node);
+        g->main_progress_node = nullptr;
+    }
+
     assert(g->errors.length != 0);
     for (size_t i = 0; i < g->errors.length; i += 1) {
         ErrorMsg *err = g->errors.at(i);

test/stage2/zir.zig

@@ -1,7 +1,15 @@
+const std = @import("std");
 const TestContext = @import("../../src-self-hosted/test.zig").TestContext;
+// self-hosted does not yet support PE executable files / COFF object files
+// or mach-o files. So we do the ZIR transform test cases cross compiling for
+// x86_64-linux.
+const linux_x64 = std.zig.CrossTarget{
+    .cpu_arch = .x86_64,
+    .os_tag = .linux,
+};
 
 pub fn addCases(ctx: *TestContext) void {
-    ctx.addZIRTransform("elemptr, add, cmp, condbr, return, breakpoint",
+    ctx.addZIRTransform("elemptr, add, cmp, condbr, return, breakpoint", linux_x64,
         \\@void = primitive(void)
         \\@usize = primitive(usize)
         \\@fnty = fntype([], @void, cc=C)
@@ -12,10 +20,11 @@ pub fn addCases(ctx: *TestContext) void {
         \\
         \\@entry = fn(@fnty, {
         \\  %a = str("\x32\x08\x01\x0a")
-        \\  %eptr0 = elemptr(%a, @0)
-        \\  %eptr1 = elemptr(%a, @1)
-        \\  %eptr2 = elemptr(%a, @2)
-        \\  %eptr3 = elemptr(%a, @3)
+        \\  %aref = ref(%a)
+        \\  %eptr0 = elemptr(%aref, @0)
+        \\  %eptr1 = elemptr(%aref, @1)
+        \\  %eptr2 = elemptr(%aref, @2)
+        \\  %eptr3 = elemptr(%aref, @3)
         \\  %v0 = deref(%eptr0)
         \\  %v1 = deref(%eptr1)
         \\  %v2 = deref(%eptr2)
@@ -34,7 +43,8 @@ pub fn addCases(ctx: *TestContext) void {
         \\})
         \\
         \\@9 = str("entry")
-        \\@10 = export(@9, @entry)
+        \\@10 = ref(@9)
+        \\@11 = export(@10, @entry)
     ,
         \\@0 = primitive(void)
         \\@1 = fntype([], @0, cc=C)
@@ -42,66 +52,161 @@ pub fn addCases(ctx: *TestContext) void {
         \\  %0 = return()
         \\})
         \\@3 = str("entry")
-        \\@4 = export(@3, @2)
+        \\@4 = ref(@3)
+        \\@5 = export(@4, @2)
         \\
     );
 
-    if (@import("std").Target.current.os.tag != .linux or
-        @import("std").Target.current.cpu.arch != .x86_64)
+    if (std.Target.current.os.tag != .linux or
+        std.Target.current.cpu.arch != .x86_64)
     {
         // TODO implement self-hosted PE (.exe file) linking
         // TODO implement more ZIR so we don't depend on x86_64-linux
         return;
     }
 
-    ctx.addZIRCompareOutput("hello world ZIR",
-        \\@0 = str("Hello, world!\n")
-        \\@1 = primitive(noreturn)
-        \\@2 = primitive(usize)
-        \\@3 = fntype([], @1, cc=Naked)
-        \\@4 = int(0)
-        \\@5 = int(1)
-        \\@6 = int(231)
-        \\@7 = str("len")
-        \\
-        \\@8 = fn(@3, {
-        \\  %0 = as(@2, @5) ; SYS_write
-        \\  %1 = as(@2, @5) ; STDOUT_FILENO
-        \\  %2 = ptrtoint(@0) ; msg ptr
-        \\  %3 = fieldptr(@0, @7) ; msg len ptr
-        \\  %4 = deref(%3) ; msg len
-        \\  %sysoutreg = str("={rax}")
-        \\  %rax = str("{rax}")
-        \\  %rdi = str("{rdi}")
-        \\  %rsi = str("{rsi}")
-        \\  %rdx = str("{rdx}")
-        \\  %rcx = str("rcx")
-        \\  %r11 = str("r11")
-        \\  %memory = str("memory")
-        \\  %syscall = str("syscall")
-        \\  %5 = asm(%syscall, @2,
-        \\    volatile=1,
-        \\    output=%sysoutreg,
-        \\    inputs=[%rax, %rdi, %rsi, %rdx],
-        \\    clobbers=[%rcx, %r11, %memory],
-        \\    args=[%0, %1, %2, %4])
-        \\
-        \\  %6 = as(@2, @6) ;SYS_exit_group
-        \\  %7 = as(@2, @4) ;exit code
-        \\  %8 = asm(%syscall, @2,
-        \\    volatile=1,
-        \\    output=%sysoutreg,
-        \\    inputs=[%rax, %rdi],
-        \\    clobbers=[%rcx, %r11, %memory],
-        \\    args=[%6, %7])
-        \\
-        \\  %9 = unreachable()
-        \\})
-        \\
-        \\@9 = str("_start")
-        \\@10 = export(@9, @8)
-    ,
-        \\Hello, world!
-        \\
+    ctx.addZIRCompareOutput(
+        "hello world ZIR, update msg",
+        &[_][]const u8{
+            \\@noreturn = primitive(noreturn)
+            \\@void = primitive(void)
+            \\@usize = primitive(usize)
+            \\@0 = int(0)
+            \\@1 = int(1)
+            \\@2 = int(2)
+            \\@3 = int(3)
+            \\
+            \\@syscall_array = str("syscall")
+            \\@sysoutreg_array = str("={rax}")
+            \\@rax_array = str("{rax}")
+            \\@rdi_array = str("{rdi}")
+            \\@rcx_array = str("rcx")
+            \\@r11_array = str("r11")
+            \\@rdx_array = str("{rdx}")
+            \\@rsi_array = str("{rsi}")
+            \\@memory_array = str("memory")
+            \\@len_array = str("len")
+            \\
+            \\@msg = str("Hello, world!\n")
+            \\
+            \\@start_fnty = fntype([], @noreturn, cc=Naked)
+            \\@start = fn(@start_fnty, {
+            \\  %SYS_exit_group = int(231)
+            \\  %exit_code = as(@usize, @0)
+            \\
+            \\  %syscall = ref(@syscall_array)
+            \\  %sysoutreg = ref(@sysoutreg_array)
+            \\  %rax = ref(@rax_array)
+            \\  %rdi = ref(@rdi_array)
+            \\  %rcx = ref(@rcx_array)
+            \\  %rdx = ref(@rdx_array)
+            \\  %rsi = ref(@rsi_array)
+            \\  %r11 = ref(@r11_array)
+            \\  %memory = ref(@memory_array)
+            \\
+            \\  %SYS_write = as(@usize, @1)
+            \\  %STDOUT_FILENO = as(@usize, @1)
+            \\
+            \\  %msg_ptr = ref(@msg)
+            \\  %msg_addr = ptrtoint(%msg_ptr)
+            \\
+            \\  %len_name = ref(@len_array)
+            \\  %msg_len_ptr = fieldptr(%msg_ptr, %len_name)
+            \\  %msg_len = deref(%msg_len_ptr)
+            \\  %rc_write = asm(%syscall, @usize,
+            \\    volatile=1,
+            \\    output=%sysoutreg,
+            \\    inputs=[%rax, %rdi, %rsi, %rdx],
+            \\    clobbers=[%rcx, %r11, %memory],
+            \\    args=[%SYS_write, %STDOUT_FILENO, %msg_addr, %msg_len])
+            \\
+            \\  %rc_exit = asm(%syscall, @usize,
+            \\    volatile=1,
+            \\    output=%sysoutreg,
+            \\    inputs=[%rax, %rdi],
+            \\    clobbers=[%rcx, %r11, %memory],
+            \\    args=[%SYS_exit_group, %exit_code])
+            \\
+            \\  %99 = unreachable()
+            \\});
+            \\
+            \\@9 = str("_start")
+            \\@10 = ref(@9)
+            \\@11 = export(@10, @start)
+        ,
+            \\@noreturn = primitive(noreturn)
+            \\@void = primitive(void)
+            \\@usize = primitive(usize)
+            \\@0 = int(0)
+            \\@1 = int(1)
+            \\@2 = int(2)
+            \\@3 = int(3)
+            \\
+            \\@syscall_array = str("syscall")
+            \\@sysoutreg_array = str("={rax}")
+            \\@rax_array = str("{rax}")
+            \\@rdi_array = str("{rdi}")
+            \\@rcx_array = str("rcx")
+            \\@r11_array = str("r11")
+            \\@rdx_array = str("{rdx}")
+            \\@rsi_array = str("{rsi}")
+            \\@memory_array = str("memory")
+            \\@len_array = str("len")
+            \\
+            \\@msg = str("Hello, world!\n")
+            \\@msg2 = str("HELL WORLD\n")
+            \\
+            \\@start_fnty = fntype([], @noreturn, cc=Naked)
+            \\@start = fn(@start_fnty, {
+            \\  %SYS_exit_group = int(231)
+            \\  %exit_code = as(@usize, @0)
+            \\
+            \\  %syscall = ref(@syscall_array)
+            \\  %sysoutreg = ref(@sysoutreg_array)
+            \\  %rax = ref(@rax_array)
+            \\  %rdi = ref(@rdi_array)
+            \\  %rcx = ref(@rcx_array)
+            \\  %rdx = ref(@rdx_array)
+            \\  %rsi = ref(@rsi_array)
+            \\  %r11 = ref(@r11_array)
+            \\  %memory = ref(@memory_array)
+            \\
+            \\  %SYS_write = as(@usize, @1)
+            \\  %STDOUT_FILENO = as(@usize, @1)
+            \\
+            \\  %msg_ptr = ref(@msg2)
+            \\  %msg_addr = ptrtoint(%msg_ptr)
+            \\
+            \\  %len_name = ref(@len_array)
+            \\  %msg_len_ptr = fieldptr(%msg_ptr, %len_name)
+            \\  %msg_len = deref(%msg_len_ptr)
+            \\  %rc_write = asm(%syscall, @usize,
+            \\    volatile=1,
+            \\    output=%sysoutreg,
+            \\    inputs=[%rax, %rdi, %rsi, %rdx],
+            \\    clobbers=[%rcx, %r11, %memory],
+            \\    args=[%SYS_write, %STDOUT_FILENO, %msg_addr, %msg_len])
+            \\
+            \\  %rc_exit = asm(%syscall, @usize,
+            \\    volatile=1,
+            \\    output=%sysoutreg,
+            \\    inputs=[%rax, %rdi],
+            \\    clobbers=[%rcx, %r11, %memory],
+            \\    args=[%SYS_exit_group, %exit_code])
+            \\
+            \\  %99 = unreachable()
+            \\});
+            \\
+            \\@9 = str("_start")
+            \\@10 = ref(@9)
+            \\@11 = export(@10, @start)
+        },
+        &[_][]const u8{
+            \\Hello, world!
+            \\
+        ,
+            \\HELL WORLD
+            \\
+        },
     );
 }